Eco-friendly design/synthesis of nano-oxides: control of size, shape, morphology

and functionalization of ZnOby polysaccharides assisted methodologies

(2011-2016)

Financed: UEFSCDI

PN-II-ID-PCE-2011-3-0473 (contract no. 17/2011)

TeamProject leader:

Dr. Oana Carp- Institute de of Physical-Chemistry “Ilie Murgulescu”, Bucharest

Team’s members: Dr. Greta Socoteanu (Patrinoiu)- Institute de of Physical-Chemistry “Ilie Murgulescu”, BucharestDr. Diana Visinescu - Institute de of Physical-Chemistry “Ilie Murgulescu”,

Bucharest,Dr. Jose Maria Calderon-Moreno- Institute de of Physical-Chemistry

“Ilie Murgulescu”, BucharestDr. Adina Magdalena Musuc- Institute de of Physical-Chemistry “Ilie Murgulescu”,

BucharestDr. Raluca Voda-Universty –University “Politehnica” Faculty for Industrial

Chemistry and Environmental Engineering, TimisoaraMasterand Raluca Florentina Negrea- National Institute of Material Physics, BucharestDr. Ruxandra Bârjega-National Institute for Lasers, Plasma and Radiation Physics,

BucharestDr. Cornel Munteanu- Institute de of Physical-Chemistry “Ilie Murgulescu”, BucharestDr. Adina Magdalena Musuc-Institute de of Physical-Chemistry “Ilie Murgulescu”, BucharestMasterand/Ph-student Alina Stan- Institute de of Physical-Chemistry “Ilie Murgulescu”

employed by competition on a free position of the project

TeamProject leader:

Dr. Oana Carp- Institute de of Physical-Chemistry “Ilie Murgulescu”, Bucharest

Team’s members: Dr. Greta Socoteanu (Patrinoiu)- Institute de of Physical-Chemistry “Ilie Murgulescu”, BucharestDr. Diana Visinescu - Institute de of Physical-Chemistry “Ilie Murgulescu”,

Bucharest,Dr. Jose Maria Calderon-Moreno- Institute de of Physical-Chemistry

“Ilie Murgulescu”, BucharestDr. Adina Magdalena Musuc- Institute de of Physical-Chemistry “Ilie Murgulescu”,

BucharestDr. Raluca Voda-Universty –University “Politehnica” Faculty for Industrial

Chemistry and Environmental Engineering, TimisoaraMasterand Raluca Florentina Negrea- National Institute of Material Physics, BucharestDr. Ruxandra Bârjega-National Institute for Lasers, Plasma and Radiation Physics,

BucharestDr. Cornel Munteanu- Institute de of Physical-Chemistry “Ilie Murgulescu”, BucharestDr. Adina Magdalena Musuc-Institute de of Physical-Chemistry “Ilie Murgulescu”, BucharestMasterand/Ph-student Alina Stan- Institute de of Physical-Chemistry “Ilie Murgulescu”

employed by competition on a free position of the project

Generally, the polysaccharide polymer ability to capture, bind and thus preorganizing metal ions, provides preferred nucleation and crystal growth constrained to nanoscale, allowing morphology control and preventing spontaneous particles agglomeration if the crystalline oxide is formed in solution, or sintering, if heating treatment are required for oxide crystallization. The polysaccharides interference in oxide synthesis occur in various stage of synthesis and depend both on intrinsic features like raw materials nature and extrinsic ones materialized in tunable reaction conditions. Since the project aims to analyze how polysaccharides properties may control the design/synthesis of oxide materials under various extrinsic factors, the synthetic methodology was chosen as methodological criterion. For each synthetic procedure, an in-depth characterization of the precursor, its conversion to oxide (if the reaction proceed via a precursor) and of the obtained oxide will be performed, taking advantage of the complementary scientific competences of the research team. Thus, the precursor will be characterized by elemental analysis and FTIR spectroscopy, the precursor→oxide conversion by thermal analysis, while the obtained oxide by optical (FTIR, UV-Vis, PL, Raman spectroscopy), structural (XRD), morphological (SEM, TEM, HRTEM) and specific surface investigations. The different developed synthetic approaches are focused on the synthesis of ZnO materials of nanomeric sizes and various morphologies and functionalizations using polysaccharides build up from D-glucose units linked either by α-glycosidic bonds (starch and dextran) and β-bonds (methyl-cellulose) as raw materials. The choice of these systems is not accidental. Thus, the chosen methodologies can be developed toward eco-friendly approaches, through improving their atom and energy economical (high-yield with small amounts of by-products, low energy consumption, room or low-temperatures synthesis) and minimizing hazard effect on human health and environmental (nontoxic, low cost and bio-renewable raw materials), permitting also a reliable control of the oxide products (crystallinity, purity, size, shape, morphology, functionalization) without compromising their quality, on the contrary improving it. The selected polysaccharide will allow for the first time to accomplish a comparative study concerning the dependence of oxide characteristics on polysaccharides properties. Thus, the effect of the glycosidic bond position (α and β), the polymerization degree, hydrocarbonate chain branching and distinct rheological properties will be equally analyzed. On the other hand, ZnO plays an outstanding role in many aspects of science and engineering due to its unique optical, semiconducting, catalytic and piezoelectric properties. The oxides remarkable properties, tunable through size, morphology, and functionalization, are the starting point for attractive potential applications.

AbstractAbstract

The project implementation planYear Objectives Activities Results

2011 Design/synthesis of ZnO nanostructures: solvent, surfactants and additives influence

The synthesis of different ZnO structures: preliminary results

-Rapport

2012 Design/synthesis of ZnO nanostructures by precipitative and combustion procedures

-The influence of synthesis experimental parameters on ZnO morphological and structural properties-Photoluminescence and photocatalytical properties

-Book chapter-article-participation to national and international conferences

2013 Design/synthesis of ZnO nanostructures by hydrothermal procedures using polysaccharides as hard-template

- The influence of synthesis experimental parameters on template’s size and shape-The influence of deposition techniques on ZnO structural and morphological properties-The use of template for the synthesis of solid and hollow ZnO structures

-Book-articles-participation to national and international conferences

2014 -ZnO obtained by hydrothermal procedure using polysaccharides as soft-template-ZnO obtained by gel-template procedures using polysaccharides

-The influence of synthesis experimental parameters on ZnO morphological and structural properties-Photoluminescence and photocatalytical properties

-articles-participation to national and international conferences

2015 -ZnO obtained by forced hydrolysis procedures

-The influence of synthesis experimental parameters on ZnO morphological and structural properties-Photoluminescence and photocatalytical properties

-articles-participation to national and international conferences

2016 -ZnO obtained by gel-template procedures using polysaccharides

-The influence of synthesis experimental parameters on ZnO morphological and structural properties-Photoluminescence and photocatalytical properties

-articles-participation to national and international conferences

Used instrumentations/acquired istrumentations Institute of Physical Chemistry“Ilie Murgulescu”

UV-Vis Spectrometer PERKIN-UV-Vis Spectrometer PERKIN-ELMER LAMBDA L35, 200-ELMER LAMBDA L35, 200-

1100 nm1100 nm

PL spectrometerJASCO PL spectrometerJASCO FP-8300FP-8300

200-650 nm200-650 nm

FTIR Spectrometer JASCO FTIR Spectrometer JASCO 41004100

400-4000 cm400-4000 cm-1-1

Memmert IncubatorMemmert Incubator UNB500UNB500

Simultaneous thermal analysisSimultaneous thermal analysisSTA 449 Jupiter f1 STA 449 Jupiter f1

Acquisition of the projectAcquisition of the project

SEM MicroscopeSEM MicroscopeFEI - Quanta 3D FEG FEI - Quanta 3D FEG

Dual BeamDual Beam

TEM MicroscopeTEM MicroscopeFEI - Tecnai G2-F30 FEI - Tecnai G2-F30 coupled with EDXcoupled with EDX

UltracentrifugeUltracentrifugeAcquisition of the projectAcquisition of the project

Project obiectivesThe general scientific objective is focused on the developing

of innovative environmental friendly strategies polysaccharides-assisted, for the design and synthesis of tailor made oxide-based nanomaterials, exploiting either individually or simultaneously polysaccharides diverse and versatile properties. The project’s specific objectives that constitute also novelty features belonging both to fundamental and applicative research, are as follows: •to establish a relationship with a large degree of generalization between polysaccharide peculiarities - synthesis methodology - oxide features, in order to detect a general trend, forwarding polysaccharide-assisted design and synthesis topic;•to develop environmentally friendly protocols for the synthesis of nanosized (50-300 Å) ZnO materials, functionalized or not with polysaccharides; •to develop environmentally friendly protocols for the synthesis of ZnO spherical structures such as sphere, core/shell, hollow sphere and jingle-bell;•to develop environmentally friendly protocols for the synthesis of ZnO/C composites.

Besides these scientific objectives (original results in areas of interest and perspective), objectives like international visibility increasing (by publication in journal of high impact factor and participation to prestigious international conference), young researchers motivation (by financial advantages) as well as infrastructure improvement and supplies purchase have to be mentioned.

Budget Breakdown

No. Budget chapter (expens

es)

2011 2012 2013 2014 2015 2016 Total

1. Salaries 25 000 110 000 80 000 30 000 68 268 127 732 440 693.5

2. Inventory 46752.6 285 247.4 74 182.2 54 571.55 30 492 39 837.44 259 999.99

3. Mobility 0 45 000 7000 928.45 16 000 22 500 91 086.99

4. Overhead 18 247.4 109 752.6 40 295.5 21 375 37 700 9 117. 77 508 219.52

5. Total 90 000 550 000 201 477.7 106 875 152 460 199 187.21

1 300 000

1. The synthetic protocols : the building green methodologies

2. Polysaccharides as soft templates for ZnO: precipitation synthetic protocols

2.1 Zn2+-starch system: model system

2.2. Zn2+-methylcellulose Zn2+-dextran systems

3. Polysaccharides as combustion agents for ZnO

4. Polysaccharides as hard templates for ZnO spherical structures:

4.1 Template synthesis

4.2 Synthesis, characterization and applications of ZnO hollow spheres

4.2.2 Impregnation deposition method

4.2.3 Ultrasound deposition method

4.3 Synthesis, characterization and applications of ZnO solid spheres

4.4. Synthesis, characterization and applications of ZnO/C spherical structures

5. Polysaccharides as soft templates for ZnO: hydrothermal synthetic protocols

6. Forced hydrolysis precipitation

1. The synthetic protocols : the building green methodologies

Although some progress regarding the involvement of saccharides in materials synthesis has been already made, the identification, investigation and development of carbohydrates assisted synthetic routes is (unfortunately) an insufficiently explored research topic of the chemistry. Following a small steps approach, we selected for the start polisaccharides having in common the presence of D-glucose units: polysaccharides starch and dextran containing D-glucose units linked by α-glycosidic bonds and, methylcellulose constituted from D-glucose units linked by β-bonds.

zinc source

precip

itation

agent 1

pre

cipitat

ion

agen

t 2

starc

h

dextra

n

metyl-cellulose

2. The main precipitation synthetic methodologies developed with polysaccharides as soft template

Various hierarchical spherical shaped assemblies ZnO structures were successfully synthesized via a simple, low-cost starch-mediated precipitation method. It was proved that starch is the key parameter for the synthesis of pure ZnO material with spherical morphologies. The temperature increase lead to a variation of ZnO stoichiometry and implicit its associated defects that determine an interesting change of the optical properties (band gap, photoluminescence characteristics). While ZnO-starch composites obtained initially after the synthesis reaction performed at 80oC are of 5-7 spheres aggregates with diameters of 100 to 500 nm, after the calcination (500oC) their morphologies change into a donut-like ones which centered-located holes shrinks to extinction with further temperature rising (800oC). The donut morphology is connected with the highest surface area and total pore volume. The oxide obtained after calcinations at 500oC demonstrated excellent photodegradation ability under visible light irradiation, a total mineralization of phenol being achieved. Such properties is caused by a combination of relatively significant specific surface area due to its donut morphology, high crystallinity and a favorable combination of defects for band narrowing that permit a enhanced light utilization rate.

2.1 Zn2+-starch system: model system

2.1 Zn2+-starch system: characterization and applications

(c) (d)

(a) (b)

(c) (d)

(e) (f)

SEM images of: (a-b) ZnO_starch; (c-d) ZnO_500 and (e-f) ZnO_800

XRD patterns UV-Vis spectaPhotoluminescence

spectra Phenol conversion

XPS results for ZnO_500 and ZnO_800

O

HOH

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HOH

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[Zn(H2O)6]2+

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[Zn(H2O)6]2+

HO

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HOH

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NH4(OH)80oC 80oC

80oC 500oC 800oC

A B

CD E F

=ZnO

ZnO-starch ZnO ZnO

2.1 Zn2+-starch system: ZnO/starch formation and transformation mechanism toward ZnO

Biopolymer starch mediated synthetic route of multi-spheres and donut ZnO structures, O. Carp,A. Tirsoaga, B. Jurca, R. Ene, S. Somacescu, A. Ianculescu,

Carbohydrate Polymers, 2015, 115 (22), 285-293 4 citations

2.1 Zn2+-starch system: influence of synthesis parameters (time, temperature, ultrasound irradiation)

The thermal behavior of the ZnO-starch composites consists in three decomposition stages, a dehydration assigned to water evolving and a two-step starch degradation, followed by phase transformation processes assigned to ZnO the crystallization and crystal growth. The starch decomposition is different comparative with pure starch. The degradation occurs at lower temperature ranges being associated with an inferior exothermic effect, behavior attributed to the catalytic effect of ZnO. The registered starch content is explained as a result of two processes, starch homogenization in reaction medium, and Zn2+-starch complex thermal stability. The nucleation and crystal growth processes of ZnO that follow the burning of the carbonaceous materials occur at higher temperatures than in bulk oxide.

300 400 500

endo

exo

D90T

D80T

D100T

(a)

300 400

(b)

DG80T

DG90T

DG100T

200 300 400

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200 300 400

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A s

igna

l/a.u

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DG6U

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exo

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500 600 700

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G100T

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500 600

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igna

l/a.u

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D6U

DTA curves of ZnO-starch composites corresponding to starch decomposing : (a) predissolved starch and

heated 80-100oC (DT); (b) pregelatinezed starch and heated 80-100oC (GT); (c) predissolved or pregelatinezed starch 25 min, ultrasound (D/G15U); (d) predissolved or

pregelatinezed starch, 6 h ultrasound (D/G6U).

DTA curves of ZnO-starch composites corresponding to ZnO nucleation/growth : (a) predissolved starch and heated 80-100oC (DT); (b) pregelatinezed starch and

heated 80-100oC (GT); (c) predissolved or pregelatinezed starch 25 min, ultrasound (D/G15U); (d) predissolved or

pregelatinezed starch, 6 h ultrasound (D/G6U).

“Influence of the synthesis parameters on the thermal behavior of some ZnO-starch composites”, Jurca, B.,

Tirsoaga, A., Ianculescu, A., Carp, O, Journal of Thermal Analysis and Calorimetry, 2014, 115 (1), 495-50. 3 citations

2.2 Zn2+-methylcellulose and Zn2+-dextran systems

•The developed green synthetic protocols lead to diverse morphologies: spherical, spindle, rod ones. •The influence of the synthesis parameters (time, temperature, raw materials nature and ratio, precipitation agent, initial pH and its evolution during the synthesis, ultrasound irradiation) on the shape, size and porosity of the obtained ZnO-based composites is investigated.• The thermoreactivity of the synthesized composites is scrutinized.•The possibility of obtaining ZnO/C composites is also analyzed, establishing the parameters of polysaccharide carbon containing materials conversion, degree of crystallization/graffitization, influence of Zn2+ amount on final material quality. •The optical properties of the ZnO based materials were analyzed by UV-Vis and photoluminescence spectroscopy.•A formation mechanism for each system was advanced, evidencing the auto-assembling processes. •The composites, either ZnO-saccharide and ZnO/C were tested as photocatalysts and antimicrobian agents, establishing different correlations between the optical properties and the efficiency in these applications.• For same composites, electrochemical investigations (linear sweep voltammetry, electrochemical activity analysis) were also performed.

One article is in preparation : Methylcellulose based synthesis for ZnO with spindle like morphologies, R.Dumitru, J.M.Calderon-Moreno, R.Birjega, O.Carp.

3. Polysaccharides as combustion agents for ZnO

SEM images of ZnO: (A) starch-Zn(NO3)2; (B) cellulose-Zn(NO3)2; (C) starch-Zn(CH3COO)2; (D) cellulose-Zn(CH3COO)2

In this synthetic procedure the polysaccharides act as high temperature fuels. The obtained ZnO crystallites are larger than those obtained by precipitate method, the specific surface lower (2-4 m2 /g), but the activity in photocatalytic degradation reactions tested for phenol and resorcinol are particularly good, a 100% mineralization of pollutants being achieved. The obtained data are the subject of an article in preparation.

One article is in preparation : Starch and cellulose as combustion agents in ZnO synthesis with enhanced photocatlytical activity, O.Carp, R.Ene, A.Tarsoaga, R.Birjega,.

4. Polysaccharides as hard templates for ZnO spherical structures: Hard templates syntheses are generally used for obtaining hollow structures.

In principle, regardless of the used methodology, the synthesis procedure should include three stages:- hard-template synthesis;-introduction /deposition on template surface of the metallic cations;- the remove of the hard-template by further processing (usually thermal ones). We utilized several introduction techniques as impregnation, ultrasound irradiation, or a double deposition (impregnation and impregnation). The diameter and the wall thickness of the obtained spherical morphology, its type (solid or hollow) and porosity depend on the synthesis and calcination parameters.

Our research showed for the first time that the template generated by polysaccharides can also function as a template in obtaining solid oxide spherical structures (solid spheres) and also for metal oxide / C composites preserving the same morphology.

The scheme of hydrothermal process SEM images of carbonaceous sphere templates

4.1 Template synthesis

4 .2 Polysaccharides as hard templates for ZnO spherical structures:

synthesis, characterization and applications of hollow structures

4.2.1 Deposition: impregnation method

SEM images of Zn2+/carbonaceous template

and ZnO hollow sphere

„A green chemical approach to the synthesis of photoluminescent ZnO hollow spheres with enhanced photocatalytic properties”, G. Patrinoiu, M.Tudose, J.M.Calderon-Moreno, R.Birjega,

P.Budrugeac, R.Ene, O.Carp, J. Solid State Chem. 2012, 186, 17-22. 36 citations TOP Most downloaded 25 articles

Thermal curves of Zn2+/carbonaceous composite XRD of ZnO hollow sphere

PL spectra of ZnO hollow

sphere

Photocatalytical activity in

degradation/mineralization of phenol

3.2 Polysaccharides as hard templates for ZnO spherical structures:

synthesis, characterization and applications of hollow structures

3.2.2. Deposition: ultrasound method

TEM images of ZnO hollow sphere: (a) 3oC/min and (b) 20oC/min

BET and PL spectra of ZnO hollow sphere: (a) 3oC/min and (b) 20oC/min

Thermal curves of the precursor

(a) air and (b) argon.

XRD of ZnO hollow sphere: (a) 3oC/min and (b)

20oC/min

Photocatalytical activity

in degradation of MB under

visible irradiation

“Eco-friendly synthetic route for layered zinc compound and its conversion to ZnO with photocatalytical properties”, G.Patrinoiu, J.M. Calderon-Moreno,D.C. Culita, R.Birjega, R.Ene, O.Carp, Solid

State Sciences, 2013, 23, 58-64 5 citations ” Carbonaceous spheres: versatile intermediary of metal oxide spherical structures synthesis“ autori G.Patrinoiu, J. M. Calderon-Moreno, S. Somacescu, N. Spataru, A. M. Musuc, R. Ene, R.

Birjega, O. Carp, Eur.J.Inorg.Chem. 2014, 1010-1019. 2 citations

Polysaccharides as hard templates for ZnO spherical structures:

synthesis, characterization and applications of solid structures

4.3 Deposition: impregnation and ultrasound methods

Mechanism of solid ZnO spheres formation TEM images of ZnO solid spheres:

(a-b)impregnation and ultrasound; (c-d) ultrasound and impregnation

Raman (A) and PL (B) spectra of the solid spheres (a:U/I and b:I/U) adsorbtion/desorbtion isotherm and pore distribution of (C) U/I and (D) I/U

Photocatalytical activity in degradation of phenol under

visible irradiation

„Carbonaceous spheres-an unusual template for solid metal oxide mesoscale spheres: Application to ZnO spheres” autori: G.Patrinoiu, J. M. Calderón-Moreno, D. C. Culita, R. Birjega, R. Ene, O. Carp, Journal of Solid

State Chemistry, 202, 2013, 291-299 5 citations

Polysaccharides as hard templates for ZnO spherical structures:

synthesis, characterization and applications of hollow/solid structures

4.4 The influence of saccharide nature Zn2+/saccharide content

Schematic illustration of the approach to ZnO-based spherical structures

A one-pot hydrothermal process was used for the fabrication of self-templated carbonaceous spheres with embedded zinc. Thermal processing led to the evolving of the sacri cial template and formation of ZnO spheres, either hollow or full solid. The switch from hollow to solid oxide sphere morphology is dictated by the raw materials molar ratio (Fig. 1): the change hollow 4 full solid oxide spheres is achieved at R < 2 irrespective of the carbohydrate. Hollow spheres form in the range 2 < R ≤ 20; an increase of the zinc amount in this domain does not increase the spherical shell diameter, but develops a denser and thicker shell since a greater amount of metal oxide entails a closer packing of the crystallites. Full spheres, with diameters similar to the hollow ones, form for R < 2.

SEM micrographs of sucrose-derived precursors: (a) R = 20; (b) R = 1.67; the size distribution of precursors and their corresponding oxides: (c) R = 20 and (d) R = 1.67; (e) FTIR spectra of the two precursors.

Solid vs. hollow oxide spheres obtained by hydrothermal carbonization of various types of carbohydrates,

G.Patranoiu, J.M.Calderon-Moreno, R.Birjega, O.Carp, RSC Adv., 2015, 5, 31768–31771 1 citation

SEM micrographs of (a and b, e and f, i and j, m and n) full (R = 1.67, 600 C/1 h) and (c and d, g and h, k and l, o and p) hollow (R = 20, 600 C/1 h) ZnO spheres, whole and mechanically broken: (a–d) glucose; (e–h) fructose; (i–l) sucrose; (m–p) starch; diameter distribution for (q) full and (r) hollow spheres

An additional metal incorporation leads to diverse multi-oxide spherical structures ruled by the used deposition technique and heating treatment.

SEM micrographs and elemental mapping of zinc–cobalt double-oxide spheres. (a–c) Full solid (R = 1.67, 500 C/1 h, starch) and (d–f) core–shell (R = 5, 500 C/1 h, starch)

Polysaccharides as hard templates for ZnO spherical structures:

synthesis, characterization and applications of hollow/solid structures

4.5 Starch – Zn2+ one-pot hydrothermal synthesis

A family of distinct ZnO morphologies – hollow, compartmented, core–shell and full solid ZnO spheres, dispersed or interconnected – is obtained by a simple hydrothermal route, in the presence of the starch biopolymer.

SEM micrographs of the ZnO spheres obtained after calcination of the composite precursors at 600 C for 1 h: (a and b) ZnO_0.1_1 (c and d) ZnO_0.08; (e and f) ZnO_0.06; (g and h) ZnO_0.04; (i and j) ZnO_0.02; (k and l) ZnO_0.005.

“Tunable ZnO spheres with high anti-biofilm and antibacterial activity via a simple green hydrothermal route”, G. Patrinoiu , J. M. Calderón-Moreno, C. M. Chifiriuc, C. Saviuc,R. Birjega, O. Carp, Journal of Colloid and Interface Science 462 (2016) 64–74

Polysaccharides as hard templates for ZnO spherical structures:

synthesis, characterization and applications of hollow/solid structures

Proposed mechanism for the hydrothermal processes of low zinc-content and high-zinc content samples.

Overlay of the histograms for the MFI of EB (up) and PO (down). Controls are figured in full grey and nanoparticles in black. From left to right: efflux pumps inhibitory activity of ZnO_0.5_1 against B. subtilis; cellular coatings permeabilization induced by ZnO_0.02 against S. aureus; efflux pumps inhibitory activity and cellular coatings permeabilization induced by ZnO_0.5_1 against S. aureus.

ZnO spheres showed excellent bactericidal potential against both Gram-positive and Gram-negative bacterial strains, including ESKAPE pathogens, in planktonic and adherent, biofilm state. The ZnO solid microspheres aggregated in a three dimensional network exhibited higher antimicrobial activity than the ZnO hollow spheres, several clinical strains being more susceptible than the reference ones to the obtained ZnO materials. The flow cytometry analysis demonstrated that the tested nanoparticles act by inducing cellular wall permeabilization and efflux pumps inhibitory activity, suggesting their potential use not only as a known antimicrobial agent, but also for the restauration of antibiotics efficiency against resistant strains harboring an efflux mechanism. The antimicrobial activity dependent on ZnO morphology and content, suggests the promising ability of these materials for developing novel bacteriostatic/bactericidal/anti-biofilm agents, including the development of sanitizing formulae for disinfecting and sterilizing agents for water and different surfaces, as well as active antimicrobial coatings for medical devices.

Polysaccharides as hard templates and carbon source for metal oxide/C spherical structures:4.6 synthesis, characterization and applications of ZnO/C structures

XRD, adsorbtion/desorbtion isotherm and pore distribution and Raman spectra of the solid ZnO/C spheres

Proba Energii de legatura, eV concentratie atomica relativa

at%C1s O1s Zn2p3/2 ZnLMM C O Zn

ZnO/C 284,8 (C-C)

286.5( OH-C-O)

289.6 (C=O)

531.5 (O2-)

533.4 (OH-C-O,

C=O)

1022.5 499.2 84 8.8 7.2

ZnO/C

1 min sputtering

284,8 (C-C)

286.5( OH-C-O)

289.6 (C=O)

531.3 (O2-)

533.3 (OH-C-O,

C=O)

1022.5 498.9 82.3 8.3 9.4

ZnO/C

5 min sputtering

284,8 (C-C)

286.5( OH-C-O)

531.2 (O2-)

533.0 (OH-C-O,

C=O)

1022.5 498.7 83.0 6.8 10.2

XPS data: binding energies, chemical species, atomic relative concentrations

” Carbonaceous spheres: versatile intermediary of metal oxide spherical structures synthesis“ autori G.Patrinoiu, J. M. Calderon-Moreno, S. Somacescu, N. Spataru, A.

M. Musuc, R. Ene, R. Birjega, O. Carp, Eur.J.Inorg.Chem. 2014, 1010-1019 2 citations

Thermal curves,

photocatalytical activy (phenol) and specific

capacitance

5. Polysaccharides as soft templates for ZnO/saccharide composites

The developed one-pot synthetic procedure is green both regarding utilized raw materials [zinc acetate as zinc source, carbohydrates (glucose, fructose, sucrose, dextran, starch and methylcellulose)as growth inhibitors and crystal habit modifiers], and synthetic methodology (mild hydrothermal procedure carried out at low temperature for a short period of time). The general character of the method derives from the possibility of using either mono, di- or polysaccharides that contains D-glucose units. Because the nature of the saccharide rules the construction features of the ZnO structures (rods spindles, hollow and solid spheres), the ability to use various carbohydrates adds to this method a high versatility. The enhanced photocatalytical and antimicrobial performances indicate the great potential of the ZnO based composites in relevant water detoxification and biomedical applications. Correlating the ZnO_SAC antimicrobial activity with the photocatalytical one, and also with their photoluminescence peculiarities we were able to identify that the mechanism of the biocidal action toward the two investigated bacterial strains follows different paths.

“A general, eco-friendly synthesis procedure of self-assembled ZnO-based materials with multifunctional properties”, A.Stan, C.Munteanu, R.Ene, E.M.Anghel, A.M. Musuc, R.Birjega, A. Ianculescu, I.Raut, L.Jecu, M.Badea Doni, O.Carp, Dalton Transactions, 2015, 44, 7844–7853

Polysaccharides as soft templates for ZnO/saccharide composites

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Grow curves of P. aeruginosa and B. subtilis in the presence of different concentrations of ZnO_SAC composites

Decoloration of MO under UV light irradiation in

the presence of: (a) ZnO_D, (b) ZnO_S, (c) ZnO_MC, (d) ZnO_ST, (e) ZnO_G, (e)

ZnO_F

Room-temperature photoluminiscence spectra of: (a)

ZnO_G, (b) ZnO_F, (c) ZnO_MC (inset ZnO_MC_500) (d) ZnO_ST,

(e) ZnO_S, (f) ZnO_D

Absorption spectra of: (a) ZnO_F, (b) ZnO_MC (inset ZnO_MC_500), (c) ZnO_G, (d) ZnO_S, (e) ZnO_ST, (f) ZnO_D

Raman spectra of: (a) ZnO_MC_500, (b) ZnO_MC, (c) ZnO_F, (d) ZnO_S, (e)

ZnO_ST, (f) ZnO_D, (g) ZnO_G samples within (A) 65 - 700 cm-1 and (B) 700 - 2000 cm-1 spectral ranges

5. Polysaccharides as soft templates for ZnO/saccharide composites

5. Polysaccharides as soft templates for ZnO/saccharide composites: thermoreactivity of methylcellulose composites

Thermal curves of ZnO_MC_H (a) TG (I), DTG (II), DSC (III) and Gram - Schmidt (IV) curves; (b) 3D-FTIR plot of the evolved gases

Thermal curves of ZnO_MC_PP (a) TG (I), DTG (II), DSC (III) and Gram - Schmidt (IV) curves; (b) 3D-FTIR plot of the evolved gases

Thermal curves of ZnO_MC (a) TG (I), DTG (II), DSC (III) and Gram - Schmidt (IV) curves; (b) 3D-FTIR plot of the evolved gases

FTIR spectra MC (a); ZnO_MC_H (b); ZnO_MC_PP (c); ZnO_MC(d)

SEM micrographs of (a) ZnO_MC_H; (b) ZnO_MC_PP and (c) ZnO_MC_500

“Synthesis, characterization and thermoreactivity of some methylcellulose-zinc composites”, A.M.Musuc, R. Dumitru, A.Stan, C.Munteanu, R.Birjega and O.Carp, Journal of Thermal Analysis and Calorimetry, 2015, 120 (1) 30, 85-94

6. Forced hydrolysis precipitation – polyol method

“Additive-free 1,4-butanediol mediated synthesis: a suitable route to obtain nanostructured, mesoporous spherical zinc oxide materials with multifunctional properties”, D. Visinescu, M. Scurtu, R. Negrea, R. Birjega, D. C. Culita, M. C. Chifiriuc, C. Draghici, J.M. Calderon Moreno, A. M. Musuc, I. Balint, O. Carp, RSC Advances DOI: 10.1039/c5ra20224h

A polyol procedure that affords in one-step and mild conditions, highly crystalline zinc oxide nanoparticles, aggregated in mesoporous hollow and solid spherical-shaped structures was developed. We employed 1,4-butanediol (BD), which was rarely used in oxides syntheses. The present study analyses thoroughly the mechanism of zinc oxide formation, as well as the influence of the reaction conditions (zinc source concentration and reaction time/temperature) on the final crystalline quality, morphology, surface characteristics, and thus, on the corresponding optical properties.

a b

(a) SEM panoramic micrograph (inset: magnified SEM image); (b) TEM image of a single-sphere showing the hollow internal structure (inset: corresponding SAED pattern) for the sample obtained for 0.1M Zn2+/90 oC/ 5h

a b

(a) SEM panoramic micrograph; (b) TEM micrograph (inset: magnified TEM image and the corresponding SAED pattern) for the sample obtained for 0.25 M Zn2+/90 oC/ 5h

Room-temperature emission PL spectra for the samples obnained at 90 oC/ 5h at Zn2+ concentration equal with 0.1 M, 0.25 M and 0.5 M

Forced hydrolysis precipitation – polyol methodFormation/growth mechamism

The development of different spherical ZnO morphologies

a b c

I

d fe

II

g h i

III

TEM image at low magnification (a, d, g), HRTEM micrographs centered on a particle of ZnO formed by small crystallites (b, e, h) and SAED patterns (c, f, i) for samples obtained at 0.25 M zinc cations concentration, at 140oC after 45 (I), 90 (II) and 180 minutes (III).

By keeping constant the Zn precursor concentration, raising the reaction temperature up to 140 oC for a shorter reaction time (2h), we obtained smaller solid ZnO nanoclusters, most likely due to a similar acceleration of the hydrolysis/dehydration processes. A longer reaction time (5h), at constant temperature and zinc content (140oC/0.25M) produces undefined agglomerates of ZnO clusters (up to ca. 50 nm). A further increase of the temperature (180 oC/5h/0.25M), yielded larger, well-defined ZnO spheres (up to 100 nm).

Forced hydrolysis precipitation – polyol method

Time course of reactant (NO3-) and

products (NO2-, NH4

+, N (N2) during denitration over organic-capped ZnO nanoparticles (as prepared, A) and over ZnO cleaned by light irradiation (B). (Sample synthesis parameters 0.25M Zn2+/180 oC, BD)

Photocatalytical investigations

Time course of CO2 formation through photocleaning (Sample synthesis parameters 0.25M Zn2+/180 oC, BD)

The photocatalytical experiments are related to the presence of the organic coatings on the ZnO surface and were performed in order to: (i) use the light irradiation as an alternative possibility for surface cleaning and (ii) exploit the organic moieties as hole scavengers in photocatalytical reduction reaction of NO3

-.

The exploration of the photocatalytic activity under visible irradiation, gave remarkable results in the denitration reaction in terms of nitrate conversion and N2 selectivity, highlighting the importance of the capping organic species. This opens new perspectives in developing performant “two in one” formula photocatalysts, namely a wide-band semiconductor with an organic coating that works as hole scavenger.

Forced hydrolysis precipitation – polyol method Antimicrobial investigations

Gram-positive strains

MIC MBECGram-

negative strains

MIC MBEC

S. aureus ATCC 6538

250 500P.

aeruginosa ATCC 27853

62.5 31.25

MRSA 125 500P.

aeruginosa 719

62.5 500

B. subtilis ATCC 12488

250 62.5 E. coli ATCC 13202 250 500

B. subtilis 6683 125 500 E. coli 634 500 500

MIC and MBEC values (μg mL-1) of the tested compounds on the Gram-positive and Gram-negative reference and

clinical strains in planktonic and biofilm form.

MIC= minimal inhibitory concentrationMBEC= minimal biofilm eradication concentration

ZnO spherical morphologies proved to have good antimicrobial and anti-biofilm activities, suggesting their potential for the development of novel antimicrobial formulations. The good anti-biofilm activity against P. aeruginosa is remarkable, considering that this pathogen is one of the most powerful agent of biofilm associated infections, particularly in cystic fibrosis patients, in which it can cause particularly devastating chronic lung infections or facilitate the occurrence of life-threatening nosocomial infections in short time courses. Furthermore, biofilm cells of P. aeruginosa are much more resistant to semiconductor stress than their planktonic counter-parts.

Dissemination of project scientifically results

A green chemical approach to the synthesis of photoluminescent

ZnO hollow spheres with enhanced photocatalytic properties

Greta Patrinoiu, Madalina Tudose, Jose Maria Calderón-Moreno, Ruxandra Birjega, Petru Budrugeac, Ramona Ene, Oana Carp

Journal of Solid State Chemistry, 186, 2012, 17-22 FI= 2.04 TOP MOST DOWNLOADED PAPERS 36 citations

AbstractZnO hollow spheres have been synthesized by a simple and environmentally friendly template assisted route. Starch-derived carbonaceous spheres were used as template, impregnated with Zn(CH3COO)2·2H2O to obtain zinc-containing precursor spheres and thermally treatment at 600°C, yielding hollow ZnO spherical shells. The precursor spheres and hollow shells were characterized by X-ray diffraction, FTIR spectroscopy, scanning electron microscopy, thermal analysis and room-temperature photoluminescence measurements. The hollow spherical shells with diameters of ∼150 nm and wall thickness of ∼20 nm, are polycrystalline, with a mean crystallite size of 22 nm, exhibiting interesting emission features, with a wide multi-peak band covering blue and green regions of the visible spectrum. The photocatalytic activities (under UV and visible light irradiations) of the ZnO spherical shells evaluated for the phenol degradation reaction in aqueous solutions are outstanding, a total phenol conversion being registered in the case of UV irradiation experiments.

Keywords: Green synthesis; Hollow spheres; Phenol degradation/mineralization; Photoluminescence; ZnO

ArticleArticle

Carbonaceous spheres-an unusual template for solid metal oxide mesoscale spheres: Application to ZnO

spheres

Greta Patrinoiu, Jose Maria Calderón-Moreno, Daniela C. Culita, Ruxandra Birjega, Ramona Ene, Oana Carp

Journal of Solid State Chemistry, 202, 2013, 291-299 FI= 2.2

5 citationsAbstractA green template route for the synthesis of mesoscale solid ZnO spheres was ascertain. The protocol involves a double coating of the carbonaceous spheres with successive layers of zinc-containing species by alternating a non-ultrasound and ultrasound-assisted deposition, followed by calcination treatments. The composites were characterized by FTIR spectroscopy, thermal analysis, scanning electron microscopy while the obtained ZnO spheres by X-ray diffraction, Raman spectroscopy, scanning and transmission electron microscopy, N2 adsorption-desorption isotherms and photoluminescence investigations. A growth mechanism of the solid spheres is advanced based on these results. While the spheres’ diameters and the mean size values of ZnO are independent on deposition order, the surface area and the external porosity are fairly dependent. The photoluminescence measurements showed interesting emission features, with emission bands in the violet to orange region. The spheres present high photocatalytical activity towards the degradation of phenol under UV irradiation, the main reaction being its mineralization.

Keywords: Carbonaceous spheres, ZnO solid spheres, Ultrasound, Green synthesis

ArticleArticle

Eco-friendly synthetic route for layered zinc compound and its conversion to ZnO with photocatalytical properties

Greta Patrinoiu, Jose Maria Calderón-Moreno, Daniela C. Culita, Ruxandra Birjega, Ramona Ene, Oana Carp

Solid State Science 23, 2013, 58-64. FI=1.6795 citations

AbstractLayered basic zinc salt (LBZS) that contains both carbonate and acetate as intercalated anions was obtained by a sonochemical procedure, using a non-basic zinc acetate aqueous solution. The compound was characterized by IR spectroscopy, thermal analysis, SEM and XRD investigations. The LBZS consists in a lamellar structure with two interlayer distances (13.70 and 19.34 Ǻ), the XRD pattern and SEM images being characteristic for turbostratic materials. The acetate anions are intercalated as free anions and monodentate ligands, while carbonate anions behave as bidentate ligands. A growth mechanism for the LBZS is advanced. Its calcination at 600oC led to ZnO porous sheets with uniform pores and pore density and a BET surface of 10.9 g/m2. ZnO exhibits interesting photoluminescence features, with two multi-peaks bands covering the visible region. The UV photocatalytical activity tested for phenol degradation shows that ZnO acts as a promising photocatalyst, ~90 % of the phenol being mineralized.

Keywords: Green synthesis, Layered compounds, Zinc oxide, Photocatalyst

ArticleArticle

Influence of the synthesis parameters on the thermal behaviour of some ZnO-starch composites

Bogdan Jurca, Alina Tirsoaga, Adelina Ianculescu, Oana Carp

Journal of Thermal Analysis and Calorimetry, 2014, 115 (1), 495-50 FI= 2.042 3 citationsAbstractTen ZnO-starch composites were synthesized using a simple precipitation methodology. The IR spectroscopy and XRD investigations reveal the presence of amorphous starch and crystalline ZnO. The obtained composites present a spherical morphology, 5-8 spheres being interconnected into aggregates. The thermal analysis demonstrates that starch decomposition and ZnO thermally induced nucleation and crystal growth depend on synthesis parameters such as starch processing (dissolution or gelatinization), reaction temperature (80, 90, 100 oC), reaction time (15 minutes or 6 hours) and applied treatments (heating or ultrasound irradiation).

Keywords: ZnO, Starch , Composites , Thermoreactivity

ArticleArticle

ArticleArticleCarbonaceous spheres: versatile intermediary of metal oxide spherical structures synthesis

Greta Patrinoiu, Jose Maria Calderon-Moreno, Simona Somacescu, Nicolae Spataru, Adina M. Musuc, Ramona Ene, Ruxandra Birjega,

and Oana Carp

European Journal of Inorganic Chemistry, 2014, 1010-1019. FI=2,942

2 citationsAbstractA facile, versatile, genuine green route that uses starch-derived carbonaceous spheres as the templates and carbon source for tailor-made ZnO spherical structures is described. A simple adjustment of the thermal treatment permits the generation of either ZnO/C solid microporous spheres or ZnO hollow spheres, the later with controlled diameter and shell morphology. The spherical structures demonstrate good photocatalytic activity for the visible light degradation of methylene blue. Furthermore, ZnO/C has promising electrochemical capacitor applications and good electrochemical and mechanical stability.

Keywords: Carbohydrates , Green chemistry, Semiconductors, Template synthesis, Zinc

ArticleArticle

Synthesis, characterization and thermoreactivity of some methylcellulose-zinc composites

Adina Magdalena Musuc, Raluca Dumitru, Alina Stan, Cornel Munteanu, Ruxandra Birjega and Oana Carp

Journal of Thermal Analysis and Calorimetry, 2015, 120 (1) 30, 85-94 FI= 2.042Abstract

Two methylcellulose-ZnO and one methylcellulose-Zn2+ composites were obtained by precipitation and hydrothermal procedures. The thermal behavior of the composites was examined by simultaneous TG, DTG, DSC-FTIR thermal method. It was found that the thermal reactivity of the methylcellulose contained by the composites is strongly dependent on the composites’ synthetic procedure, but in all cases its stability is shifted toward lower temperatures. For each type of composites, the causes that lead to a change of methylcellulose thermoreactivity were highlighted. The structural, morphological and optical characteristics of the ZnO_based materials are also demonstrated.

Keywords: Methylcellulose, Zinc-methylcellulose composites, Thermoreactivity

Biopolymer starch mediated synthetic route of multi-spheres and donut ZnO structures

Oana Carp, Alina Tarsoaga, Ramona Ene, Simona Somacescu, Daniela C. Culita, Adelina Ianculescu

Carbohydrate Polymer, 2015, 115 (22), 285-293 FI= 3.916 4 citations

AbstractMulti-spheres ZnO were obtained by a simple precipitation procedure in the presence of the biopolymer starch. The starch removing associated with thermal processing induces a change of the structure to a donut-like one. The ZnO-starch composites and their calcinations products were in depth characterized by UV-Vis and Fourier transform infrared spectroscopy, room-temperature photoluminescence measurements, thermal analysis, X-ray photoelectron spectroscopy, N2 adsorption-desorption isotherms, scanning and transmission electron microscopy and, X-ray diffraction investigations. The photocatalytic activities of the ZnO structures evaluated for phenol degradation in aqueous solutions are significant, a total phenol mineralization being registered using donut-like ZnO and visible irradiation. Such a behavior is attributed to the relatively large specific surface area related to its distinctive donut morphology, high crystallinity and favorable combination of defects for band narrowing that permits an enhanced light utilization rate. A formation mechanism in which starch plays a dual role as soft and hard template for the ZnO-starch composites and corresponding oxides is advanced.Keywords: ZnO; Starch; Multi-spheres and donut structure; Visible-photocatalyst

ArticleArticle

A general, eco-friendly synthesis procedure of self-assembled ZnO-based materials with multifunctional properties

ArticleArticle

Alina Stan, Cornel Munteanu, Ramona Ene, Elena Maria Anghel,

Adina Magdalena Musuc, Ruxandra Birjega, Adelina Ianculescu, Iulia Raut, Luiza Jecu, Mihaela Badea Doni, and Oana Carp

Dalton Transactions, 2015, 44, 7844–7853 FI= 4.197

AbstractA bioinspired one-pot approach for the synthesis of ZnO - carbohydrate hierarchical architectures was developed. The synergy between a saccharide (mono, di- or polysaccharide) that contains D-glucose units and triethanolamine is the key parameter of the synthetic methodology. The morphology of the ZnO composites is dictated by the used saccharide, and rod, spindle, solid and hollow spherical-like ZnO structures are obtained varying the carbohydrate. The synthesized composites present good photocatalytical and antimicrobial activity.

ArticleArticle

Solid vs. hollow oxide spheres obtained by hydrothermal carbonization of various types of carbohydrates

Greta Patrinoiu, Jose Maria Calderon Moreno, Ruxandra Birjega and Oana Carp

RSC Adv., 2015, 5, 31768–31771 FI=3.841 citation

AbstractSaccharide derived, self-templated carbonaceous spheres with embedded Zn (and Co) were obtained by a versatile one-pot hydrothermal synthesis and proved to be multipurpose precursors for full solid or hollow oxide spheres. Saccharide/Zn2+ ratios and saccharide type affect the morphology (size, shell thickness, surface roughness) of the oxide spheres.

ArticleTunable ZnO spheres with high anti-biofilm and antibacterial activity

via a simple green hydrothermal route

G. Patrinoiu , J. M. Calderón-Moreno, C. M. Chifiriuc, C. Saviuc,R. Birjega, O. Carp

ArticleTunable ZnO spheres with high anti-biofilm and antibacterial activity

via a simple green hydrothermal route

G. Patrinoiu , J. M. Calderón-Moreno, C. M. Chifiriuc, C. Saviuc,R. Birjega, O. Carp

Abstract

A family of distinct ZnO morphologies - hollow, twin-brush, core-shell and full solid ZnO spheres, dispersed or interconnected - is obtained by a simple hydrothermal route, in the presence of the starch biopolymer. The zinc-carbonaceous precursors were characterized by infrared spectroscopy, thermal analysis and scanning electron microscopy, while the ZnO spheres, obtained after the thermal processing, were investigated by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, UV-VIS spectroscopy, photoluminescence measurements, antimicrobial, anti-biofilm and flow cytometry tests. The formation mechanism proposed for this versatile synthesis route is based on the gelling ability of amylose, one of the starch template constituents, responsible for the effective embedding of zinc cations into starch prior to its hydrothermal carbonization. The simple variation of the raw materials concentration dictates the type of ZnO spheres. The micro-sized ZnO spheres exhibit high antibacterial and anti-biofilm activity against Gram-positive (Staphylococcus aureus, Bacillus subtilis) and Gram-negative (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa) reference and methicillin resistant clinical strains especially for Gram-negative biofilms (Pseudomonas aeruginosa), demonstrating great potential for new ZnO anti-biofilm formulations.

Keywords: Antibacterial activity; Carbohydrates; Green chemistry; Structural design; ZnO

Journal of Colloid and Interface Science, 2016, 462, 64-74 FI= 3.368

ArticleArticle

RSC Adv., 2015, 5, 99976-99989 FI=3.84

Additive-free 1,4-butanediol mediated synthesis: a suitable route to obtain nanostructured, mesoporous spherical zinc

oxide materials with multifunctional properties

D. Visinescu, M. Scurtu, R. Negrea, R. Birjega, D. C. Culita, M. C. Chifiriuc, C. Draghici, J.M. Calderon Moreno, A. M. Musuc, I. Balint,

O. Carp

AbstractA family of mesoporous, self-aggregated zinc oxide materials with spherical morphologies of high crystalline quality, is obtained through a facile, additive-free polyol procedure. The forced hydrolysis of zinc acetylacetonate in 1,4-butanediol (BD), in various reaction conditions, affords ZnO materials with versatile morphologies and optical properties. The reaction parameters (temperature, time and zinc source concentration) modulate the ZnO nanocrystallites size (from 8.1 to 13.2 nm), the spheres diameter (ranging from 50 up to 250 nm), the internal structure of the spherical aggregates (hollow or solid) and their specific surface area (from 31 to 92 m2/g). Polycrystalline spheres with hollow cores are obtained at the lowest temperature (90oC) and zinc cation concentration (0.1 M), while at higher reaction temperatures (140-180oC), solid spherical aggregates are developed. A reaction mechanism for ZnO formation via zinc layered hydroxide (LDH-Zn) is proposed based on the nuclear magnetic resonance (1H NMR and 13C NMR) and powder X-ray diffraction (XRD) studies. The obtained ZnO materials have a functionalized surface, derived from the polyol solution and act as nitrogen selective photocatalyst in the reduction reaction of NO3

-. The organic residua attached on the ZnO surface play a crucial role in the denitrification reaction, since the photo-cleaned sample showed a negligible photocatalytic activity. The ZnO materials also exhibited microbicidal and anti-biofilm activity against reference and clinical strains, highlighting their potential for the development of novel antimicrobial formulation.

Polysaccharides route: a new green strategy for metal oxides synthesis

Diana Visinescu, Greta Patrinoiu, Alina Tirsoaga, Oana Carp

In “Environmental Chemistry for Sustainable World”, Eds: E.Lichtfouse, J.Scharzbauer, D.Roberts, Vol I. Nanotechnology and Health Risk, Springer , 2012, pp.119-172, ISBN 978-94-007-2441-9

Book chapter 2012Book chapter 2012

AbstractThe present paper reviews some of the most important polysaccharide-based synthetic strategies of metal oxides, highlighting the polysaccharides multitasking abilities in the synthesis of nanosized oxide particles. The perspectives but also the unexplored areas of this new and promising green chemistry topic are also examined. Keywords: polysaccharides; starch; cellulose; dextran; alginate; carrageenan; chitosan; metal oxides synthesis

Table of content1. Introduction2. Polysaccharides in our world 3. The role of the polysaccharides in metal oxides synthesis4. Starch

(Co)-precipitation synthesisSol-gel synthesisCombustion synthesisAlternative solution synthesis

5. Cellulose(Co)-precipitation synthesis

Surface sol-gel synthesisHydrothermal synthesisCombustion synthesisAlternative synthesis

6. Dextran(Co)-precipitation synthesisGel template synthesis

7.Alginate(Co)-precipitation synthesisGel-template synthesisHydrothermal synthesis

8. Chitosan(Co)-precipitation synthesisHydrothermal synthesis Post synthesis proceduresGel-template methods

9. Carrageenan10. Perspectives and conclusions

References

Book: Romanian Publishing House 2013ISBN 978-973-27-2281-7

Book: Romanian Publishing House 2013ISBN 978-973-27-2281-7

THERMAL ANALYSIS. FUNDAMENTS AND APPLICATIONS

Kinetic Analysis of Heterogenous Transformation

(in romanian)

ANALIZA TERMICĂ. FUNDAMENTE ŞI APLICAŢII

Analiza cinetică a transformărilor heterogene

Authors: Petru Budrugeac, Oana Carp, Nicolae Doca, Crişan Popescu, Titus Vlase, Eugen Segal

Book chapter 2015Book chapter 2015

Materials Obtained by Solid-State Thermal Decomposition of Coordination Compounds and Metal–Organic Coordination

Polymers 63

Oana Carp

In “Reactions and Mechanisms in Thermal Analysis of Advanced Materials”, Eds: Atul Tiwari, Baldev Raj, Wiley, 2015, pp: 63-85, ISBN: 978-1-119-11757-5

PatentPatent

Procedeu de obtinere a unor oxizi metalici complecsi si simpli

Nr.126777/30.07.2013

Authors: Oana Carp, Diana Beatrice Visinescu, Greta Mihaela Socoteanu, Alina Jurca, Madalina Tudose, Bogdan Jurca, Claudiu Octavian Mazilu, CarmenStefanescu, Andrei Cucos, Petru Budrugeac, Adelina-Carmen Ianculescu

Participation to national and international conferencesParticipation to national and international conferences2012- Greta M. Socoteanu, Madalina Tudose, Jose M. Calderón-Moreno , Ruxandra Birjega, Oana Carp, Old Starch: New Approaches on Synthesis of ZnO with Spherical Structures, 26th International Carbohydrate Symposium (ICS2012) , 22 - 27 iulie 2012, Madrid -Raluca Dumitru, Jose Calderon-Moreno, Ruxandra Barjega , Oana Carp, Zinc oxide controlled biopolymer assisted synthetic route, 4th EuCheMS Chemistry Congress, 26-30 august, 2012 Praga- Greta Socoteanu, Madalina Tudose, Jose Maria Calderón-Moreno, Ruxandra Birjega, Oana Carp, From Layered Basic Zinc Salts to ZnO Hollow Spheres by an Eco-Friendly Sonochemical Procedure, 4th EuCheMS Chemistry Congress, 26-30 august, 2012 Praga - Oana Carp, Greta Patrinoiu, Adelina Tarsoaga, Ruxandra Barjega, Jose Calderon Moreno, Adelina Ianculescu , Photoluminescent and photocatalytic properties of different ZnO morphologies controlled by biopolymer assisted routes, Structure-Property Relationships in Solid State Materials Conference, 24-29 iunie, Bordeuax- Oana Carp, Alina Tirsoaga, Paul Chessler, Viorica Pirvulescu, Adelina Ianculescu, Raluca Damian, Ultrasound assisted synthesis of zno flower-like structures and their photoluminescence and photocatalytic properties, XI International Conference on Nanostructured Materials, 26-31 august, 2013, Rhodos

2013 -Adina Magdalena Musuc, Alina Stan, Raluca Dumitru, Adelina Ianculescu, Oana Carp, Synthesis, characterization and thermal behaviour of some ZnO – methylcellulose composites,2-nd Central and European Conference on Thermal Analysis and Calorimetry, 27-30 august, 2013, Vilnius, Lituania-Oana Carp,Alina Tarsoaga, Adelina Ianculescu, Bogdan Jurca, Ramona Ene, ZnO obtaied by a ultrasound-assisted method in the presence of starch, Sustainable Chemical Summit, 5-7 iunie, 2013, Montreal, Canada -, Alina Stan, Adina Musuc, Adelina Ianculescu, Oana Carp, Carbohydrates-assisted synthetic routes of ZnO ROMPHYSCHEM 15, Bucuresti, 9-11 septembrie 2013-Alina Stan, Adelina Ianculescu, Adina Musuc, Oana Carp, ZnO obtained by methyl celulose-mediated synthesys, ROMPHYSCHEM 15, Bucuresti, 9-11 septembrie 2013-Adina Magdalena Musuc, Alina Stan, Adelina C. Ianculescu, Raluca Dumitru, The thermal reactivity of some ZnO-methylcellulose composites, Oana Carp, ROMPHYSCHEM 15, Bucuresti, 9-11 septembrie 2013-Diana Visinescu, Oana Carp, Raluca Negrea, Ruxandra Birjega, Jose Calderon Moreno, Mariana Scurtu, Ioan Balint, ZnO nanocrystal clusters: polyol-assisted synthesis, optical and catalytic properties, ROMPHYSCHEM 15, Bucuresti, 9-11 septembrie 2013-Greta M. Socoteanu, Jose M. Calderón-Moreno, Ruxandra Birjega, Daniela C. Culita, Simona Somacescu, Adina M. Musuc, Raluca Ene, Oana Carp, Starch-derived Carbonaceous Spheres - Versatile Templates for Spherical Structures, ROMPHYSCHEM 15, Bucuresti, 9-11 septembrie 2013- Oana Carp, Greta M. Patrinoiu, Alina Stan, Ruxandra Birjega, Jose Calderon Moreno, Nicolae Spataru, Adelina Ianculescu, Sinteze ale materialelor oxidice mediate de zaharide, Zilele Academice iesene, 3-5 octombrie, 2013

2014- Oana Carp, Greta Patrinoiu, Jose Calderon Moreno, Adina Musuc, Simona Somacescu, Ruxandra Barjega, Nicolae Spataru, Versatile metal spherical structure via carbonaceous templates, “Forth International Congress on Grenn Chemistry”, 7 – 10 aprilie 2014, Sevilia, Spania.- Oana Carp, Spherical metal oxides structures obtained by saccharide-assited synthetic routes, plenary lecture, 7th Edition of symposium with international participation - New trends and strategies in the chemistry of advanced materials with relevance in biological systems, technique and environmental protection – iunie, 5-6,Timisoara, 2014.  - Oana Carp, Saccharides-assisted synthetic routes of ZnO nanostructures, plenary lecture, Journée Franco-Roumaine, 15 iunie 2014, Brasov.

2015Oana Carp, Metallic oxides with spherical morphology obtained by green approaches, “Conferința Școlilor Doctorale din UDJG, CSSD-UDJG 2015”, 4-5 iunie 2015, Galati

TrainingTraining

-Dr. Cornel Munteanu : Transmission electron microscopy “Tecnai Basic”, 11-15 iune, 2012, Eindhoven, Olanda-Dr. Jose M.Calderon-Moreno: Transmission electron microscopy Tecnai Basic”, 11-15 iune, 2012, Eindhoven, Olanda

In work- 2014In work- 2014

In present four articles are under preparation. Their titles (provisionally) are:

-ZnO-starch: magic spheres for advanced materials -Methylcellulose based synthesis for ZnO with spindle like morphologies-Starch and cellulose as combustion agents in ZnO synthesis with enhanced photocatlytical activity-Ultrasound-assisted synthetic procedure of ZnO