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Textile dye effluents and textile waste disposal represent two significant environmental challenges. Here, we present possible combined solution for both. Urea-derived graphitic carbon nitride g-C3N4 is thermally exfoliated to nano n-C3N4. Both obtained materials are characterized in detail, and their photocatalytic efficacies in photodegradation of three textile azo dyes under simulated solar light irradiation are compared. n-C3N4 exhibited superior performance over g-C3N4 under given experimental conditions. Novelty of the work is the subsequent usage of the non-woven jute post-industrial waste as a photocatalyst support. It was shown that NW jute impregnated with n-C3N4 can be successfully used in three consecutive photocatalytic cycles, keeping high photodegradation efficacy (~ 90% in the case of Acid Orange 7, and 55% in the case of Acid Blue 113). Additionally, possibility of usage of NW jute post-industrial waste as textile dye sorbent is presented in the case of Basic Yellow 28.

Urea-based graphitic carbon nitride (g-C3N4) is thermally exfoliated at 500 °C in the airatmosphere, and nano-carbon nitride (n-C3N4) is obtained. While optical properties are assessedusing UV/Vis DR spectroscopy, structural and morphological parameters of two materials areobtained using XRD, TEM, and FTIR. Flat-band potentials were determined from Mott-Schottkyplots, and combined with corresponding band-gap energies, to estimate conduction and valenceband potentials of both materials. Photocatalytic efficacy of both semiconductors in photocatalyticdegradation of three textile dyes under simulated solar light irradiation is compared, with theconclusion that n-C3N4 expressed higher photocatalytic ability in the studied systems. Finally, inorder to provide reusability of the semiconductors in multiple consecutive photocatalytic cycles,both photocatalysts were drop-coated on the jute-based post industrial waste. Reusability of juten-C3N4 material is probed in three consecutive photocatalytic cycles, and the obtained resultsshowed that this material can have a future in solving real-life environmental problems.

Two different synthetic routes were employed to modify surface of graphitic carbon nitride (g- CN) with copper nanoparticles (CuNPs). Structure, morphology and CuNPs distribution on presynthesized g-CN surface are characterized by FT-IR, XRD and TEM. Results suggested that the simpler method based on mixing of precursors in inert atmosphere and room temperature, resulted in better CuNPs distribution compared to method which used refluxing as a step in synthesis.

Urea-based graphitic carbon nitride (g-C3N4) is thermally exfoliated at 500 °C in the air atmosphere, and nano-carbon nitride (n-C3N4) is obtained. While optical properties are assessed using UV/Vis DR spectroscopy, structural and morphological parameters of two materials are obtained using XRD, TEM, and FTIR. Flat-band potentials were determined from Mott-Schottky plots, and combined with corresponding band-gap energies, to estimate conduction and valence band potentials of both materials. Photocatalytic efficacy of both semiconductors in photocatalytic degradation of three textile dyes under simulated solar light irradiation is compared, with the conclusion that n-C3N4 expressed higher photocatalytic ability in the studied systems. Finally, in order to provide reusability of the semiconductors in multiple consecutive photocatalytic cycles, both photocatalysts were drop-coated on the jute-based post industrial waste. Reusability of juten-C3N4 material is probed in three consecutive photocatalytic cycles, and the obtained results showed that this material can have a future in solving real-life environmental problems.

Nanokompozitni prah ZrO2/Fe3O4 sintetisan je uspešno u nekoliko koraka. Prvo su sintetisane nanočestice magnetita sa zaštitnim slojem od SiO2 koji sprečava prenos elektrona iz provodne zone ZrO2 na magnetit prilikom ozračivanja. Potom je na nanočestice nanet sloj ZrO2 solvotermalnom metodom. Dobijeni prah je prečišćen uz pomoć permanentnog magneta koji obezbeđuje potpuno ukalanjanje magnetnog materijala iz rastvora. Ovako sintetisan magnetni materijal je upotrebljen kao fotokatalizator u reakcijama razgradnje 2,4 dihlorofenolai 2,4,6 trihlorofenola u vodenim rastvorima. Rezultati su pokazali da je nanokompozit efikasan adsorber i fotokatalizator za odabrana jedinjenja. Hlorofenoli su izabrani kao model jedinjenja u ovoj studiji zbog toga što se često nalaze u prirodnim vodama, u koje stižu iz pesticida koji se upotrebljavaju u poljoprivredi. Njihova toksičnost se najviše ogleda u uticaju na nervini sistem životinja i ljudi., Nanocomposite powder ZrO2/Fe3O4 was synthesized in several steps. Firstly, magnetite nanoparticles with a protective layer of SiO2 were synthesized. Silica layer protects magnetite core and prevents the transfer of electrons from the conduction band of ZrO2 to magnetite during illumination. Secondly, a layer of ZrO2 was added to the nanoparticles by the solvothermal method. The resulting powder was purified with the help of a strong magnet that ensures complete separation of the magnetic material from the solution. The magnetic material thus synthesized was used as a photocatalyst in the decomposition reactions of 2,4 dichloro- and 2,4,6 trichloro- phenols in aqueous solutions with Simulated Solar light as an irradiation source. The results showed that nanocomposite is an effective adsorber and photocatalyst for selected compounds. Chlorophenols were chosen as a model of compounds in this study because they are often found in natural waters, which come from pesticides used in agriculture. Their toxicity is mostly reflected in the impact on the nervous system of animals and humans.

U okviru ove disertacije, izvršeno je ispitivanje mogućnosti razgradnje različitih organskih zagađujućih materija, od kojih 9 iz klase organohlornih pesticida i 4 industrijske boje, lakazama iz Myceliophthora thermophila sa ekspresijom u Aspergillus oryzae (Novozym® 51003) i iz Trametes versicolor, kako slobodnim, tako i imobilisanim. Imobilizacija lakaza je vršena na neporozne nanočestice amino-funkcionalizovane nanosilike (AFNS); porozne nekomercijalne organske nosače od prirodnog materijala, odnosno dve vrste amino-modifikovanih ligninskih mikrosfera (A-LMS) i 8 komercijalno dostupnih Lifetech™ organskih, sintetskih, poroznih nosača. Primenjene metode imobilizacije bile su adsorpcija i kovalentna imobilizacija, a za sve dobijene imobilisane preparate najboljih karakteristika, iz navedenih grupa nosača, izvršena je optimizacija imobilizacije i ispitana je njihova primena u više ponovnih upotreba u razgradnji izabranih zagađivača. Kod svih ispitanih pesticida detektovana je razgradnja lakazom, a najveći stepen degradacije postignut je kod lindana, koji je korišćen kao supstrat u daljim ispitivanjima. Lakaza imobilisana na AFNS razgrađivala je lindan većom brzinom od slobodne, uz očuvanje aktivnosti, a lakaza imobilisana na A-LMS_5 imala je produženu aktivnost i degradacija lindana bila je efikasnija nego u slučaju slobodne lakaze ili lakaze imobilisane na AFNS. Iz serije Lifetech™ nosača, najbolje karakteristike pokazao je imobilisani preparat sa epoksi/butil metakrilatnim nosačem, koji je uspešno primenjen u razgradnji industrijskih boja, sa postignutim gotovo potpunim obezbojenjem uzoraka. Svi dobijeni rezultati potvrđuju velike mogućnosti primene imobilizacije lakaze, na različite kategorije nosača, u bioremedijaciji, za razgradnju organskih zagađujućih materija., In this thesis, the possibility of various organic pollutants degradation was investigated, 9 belonging to organochlorine pesticides class and 4 industrial dyes, by laccase from Myceliophthora thermophila expressed in Aspergillus oryzae (Novozym® 51003) and from Trametes versicolor, both free and immobilized. Laccase immobilization was performed onto non-porous amino-functionalized nanosilica (AFNS); porous non-commercial organic supports made of naural material - two types of amino-modified lignin microspheres (A-LMS) and 8 commercial Lifetech™ organic, synthetic, porous supports. The applied immobilization methods were adsorption and covalent immobilization. For all obtained immobilized preparations of the best characteristics, of different groups of supports, immobilization optimization was performed. Their application in several repeated uses in selected pollutants degradation was examined. Degradation by laccase was detected for all pesticides investigated. The highest degradation rate was achieved with lindane, which was used as a substrate in following experiments. Laccase immobilized on AFNS degraded lindane more rapid than free laccase, while preserving activity. Laccase immobilized on A-LMS_5 demonstrated prolonged activity, with more efficient lindane degradation than by free laccase or laccase immobilized onto AFNS. From the series of Lifetech ™ supports, the immobilized preparation with epoxy/butyl methacrylate support demonstrated best characteristics, and was successfully applied in the degradation of industrial dyes, with almost complete decolorization of the samples. All obtained results confirm the vast possibilities of laccase immobilization onto different types of supports application, in bioremediation, for the organic pollutants degradation.

Pure and a series of Fe3+ doped zirconia nanopowders were synthesized combining colloidal chemistry and solvothermal method from organometallic precursors in order to correlate doping and properties of zirconia matrix. After annealing of washed nanopowders at 600 °C, detailed characterization was performed using X-ray diffraction, UV/Vis absorption and luminescence, infrared and electron paramagnetic spectroscopy, transmission electron microscopy and BET measurements. Zirconia samples had mixed monoclinic and tetragonal crystalline phase; increasing Fe3+ ions concentration was followed by increasing of tetragonal phase share. In the sample with highest Fe3+ concentration, hematite can be detected. Also, UV/Vis spectrophotometry showed that Fe3+ doping lowers effective band gap of zirconia matrix from 4.5 eV (bulk value) to 2.1 eV for doped/nanocomposite samples. EPR measurements proved presence of dopant and showed that isolated Fe3+ ions in zirconia matrix exist in both crystalline phases; monoclinic and tetragonal (g ~ 4.8 and g ~ 4.27–4.2, respectively) surroundings. Zirconia samples were also successfully used as photocatalysts for photocatalytic degradation of 2, 4, 6, trichlorophenol.

Pure and a series of Fe3+ doped zirconia nanopowders were synthesized combining colloidal chemistry and solvothermal method from organometallic precursors in order to correlate doping and properties of zirconia matrix. After annealing of washed nanopowders at 600 °C, detailed characterization was performed using X-ray diffraction, UV/Vis absorption and luminescence, infrared and electron paramagnetic spectroscopy, transmission electron microscopy and BET measurements. Zirconia samples had mixed monoclinic and tetragonal crystalline phase; increasing Fe3+ ions concentration was followed by increasing of tetragonal phase share. In the sample with highest Fe3+ concentration, hematite can be detected. Also, UV/Vis spectrophotometry showed that Fe3+ doping lowers effective band gap of zirconia matrix from 4.5 eV (bulk value) to 2.1 eV for doped/nanocomposite samples. EPR measurements proved presence of dopant and showed that isolated Fe3+ ions in zirconia matrix exist in both crystalline phases; monoclinic and tetragonal (g 4.8 and g 4.27–4.2, respectively) surroundings. Zirconia samples were also successfully used as photocatalysts for photocatalytic degradation of 2, 4, 6, trichlorophenol. © 2019 Elsevier Ltd and Techna Group S.r.l.

beta-Galactosidase is an important industrial enzyme that catalyzes reaction of lactose hydrolysis and recently more interesting reaction of transgalactosylation, yielding a highly valuable group of prebiotic compounds named galacto-oligosaccharides (GOS). In this paper, parameters for achieving high yields of tailor-made GOS using crude beta-galactosidase obtained from Lactobacillus acidophilus ATCC 4356, probiotic bacteria regarded as safe for human consumption, were optimized. At the same time, detailed structural elucidation of obtained GOS was conducted, and it was concluded that beta-galactosidase from L acidophilus shows a particular specificity towards the formation of beta-(1 - gt 6) glycosidic bonds. In order to develop more stable and economically cost-effective preparation, crude enzyme was successfully immobilized on a methacrylic polymer carrier Lifetech ECR8409, leading to its simultaneous 2-fold purification. This immobilized preparation showed unchanged specificity towards the transgalactosylation reaction, thus yielding 86 WI GOS under the previously optimized conditions (lactose concentration 400 g/l in 0.1 M sodium phosphate buffer, pH 6.8 and temperature 50 degrees C).

Solvothermal synthesis of ZrO2-TiO2 binary oxides and pure counterparts at 150 degrees C in water/isopropanol media is presented. Titanium (IV) isopropoxide and zirconium (IV) propoxide were used as precursors. XRD and TEM techniques were used for structural and morphological characterization of obtained samples. XPS spectra of mixed oxide samples were compared in order to correlate composition of samples with surface properties and presence of defects. Relative positions of defect states within band-gaps of semiconductors were estimated from UCPL spectra. UV-Vis DRS spectra revealed that both pure oxides experienced red shift of absorption thresholds compared to reference data. Photocatalytic activities of all samples were probed under simulated Solar light on three model compounds: phenol, 4-chlorophenol (4-CP) and 2, 4, 6-trichlorphenol (TCP). Pure TiO2 showed the highest photocatalytic activity in the case of phenol. However, pure ZrO2 and binary oxides showed higher photoactivity in degradation of 4-CP and TCP. The activity of wide band-gap semiconductors under simulated Solar light in photodegradation of phenol and its derivatives is most probably the consequence of formation of charge transfer complexes between pollutant molecules and semiconductors surface.

Lipophilic derivatives of vitamin C are additives with antioxidant properties, attractive for application in food, cosmetics and pharmaceutics. They could be synthesized in lipase-catalyzed processes by using various acyl donors. Hereby, we present application of linoleic acid, which is polyunsaturated fatty acid essential in human nutrition, for esterification of vitamin C catalyzed by immobilized enzyme preparation Novozym® 435 in acetone. Highest specific ester yield, 9.7 mmol/g of immobilized lipase, was accomplished with 0.15 M of vitamin C, 0.6 M of linoleic acid, 3 g/l of enzyme and 0.07% (v/v) of water, at 60°C. NMR analyses of purified product proved that synthesized molecule was identical to 6-O-ascorbyl linoleate. Capacity of ester for scavenging 2,2-diphenyl-1-picrylhydrazyl radicals was two times higher comparing to parent molecule, vitamin C. Its diffusion coefficient, determined using Franz cell and cellulose acetate membrane, was 40% higher than palmitate and 62% higher than oleate. Obtained results showed that L-ascorbyl linoleate could be successfully synthesized in biocatalyzed processes. Furthermore, it was demonstrated that it possess high potential for application in different lipophilic products due to its liposolubility, high antioxidant efficiency and good diffusion properties., Lipofilni derivati vitamina C su aditivi sa antioksidativnim dejstvom pogodni za primenu u prehrambenim, kozmetičkim i farmaceutskim proizvodima. Mogu biti sintetisani u procesima katalizovanim lipazama korišćenjem različitih acil-donora. U ovom radu, opisana je primena linolne kiseline, polinezasićene masne kiseline esencijalne u ljudskoj ishrani, u esterifikaciji vitamina C katalizovanoj imobilisanim enzimskim preparatom Novozym® 435 u acetonu. Najviši specifični prinos estra od 9,7 mmol/g imobilisane lipaze, ostvaren je sa 0,15 M vitamina C, 0,6 M linolne kiseline, 3 g/l enzima i 0,07 zapr. % vode, na 60°C. NMR analize prečišćenog proizvoda dokazale su da je sintetisani molekul identičan 6-O-askorbil-linolatu. Kapacitet estra za vezivanje 2,2- difenil-1-pikrilhidrazil radikala bio je dva puta viši u odnosu na sam vitamin C. Njegov koeficijent difuzije, određen korišćenjem Franz-ove ćelije i celuloza-acetatne membrane, bio je za 40% viši u odnosu na palmitat i za 62% u odnosu na oleat. Ostvareni rezultati pokazali su da L-askorbil-linolat može uspešno biti sintetisan u biokatalizovanom procesu. Pored toga, dokazano je da ovaj estar poseduje značajan potencijal za primenu u različitim lipofilnim proizvodima zbog svoje liposolubilnosti, snažnog antioksidativnog dejstva i pogodnih difuzionih karakteristika.

A serie of novel ZrO2/Polyaniline (PANI) hybrid nanocomposite powders were successfully synthesized by the oxidative polymerization of aniline with ammonium peroxydisulfate (APS) in water, in the presence of ZrO2 nanoparticles. Syntheses were performed at initial ZrO2/aniline mole ratios 50,100 and 150 to produce ZP-50, ZP-100 and ZP-150. The morphological, structural, and optical properties of the synthesized nano composites were studied using Transmission electron microscopy (TEM), X-ray powder diffraction (XRD), Raman, UV-Vis and Electron-paramagnetic resonance (EPR) spectroscopies. EPR spectra of ZP-50 and ZP-100 nanocomposites showed the presence of intensive peak at the g-values comparable to that for free electrons (2.0023) indicating the presence of oligo/poly (semiquinone radical cations), i.e. polarons as charge carriers in PANI part; ZP-150 showed weak polaron peak of PANI, and peak that can be assigned to defects in zirconia matrix (Zr3+, oxygen vacancies). The monoclinic crystal structure of ZrO2 nanoparticles in all nanocomposites was confirmed by XRD and by Raman spectroscopy. The photocatalytic activities of ZP nanocomposites were evaluated using the photocatalytic degradation of trichlorophenol (TCP) and Rhodamine B model compounds and compared with the activity of bare ZrO2 nanoparticles. Enhanced degradation efficiencies of nanocomposites regarding TCP degradation were observed. (C) 2017 Elsevier B.V. All rights reserved.

A serie of novel ZrO2/Polyaniline (PANI) hybrid nanocomposite powders were successfully synthesized by the oxidative polymerization of aniline with ammonium peroxydisulfate (APS) in water, in the presence of ZrO2 nanoparticles. Syntheses were performed at initial ZrO2/aniline mole ratios 50,100 and 150 to produce ZP-50, ZP-100 and ZP-150. The morphological, structural, and optical properties of the synthesized nano composites were studied using Transmission electron microscopy (TEM), X-ray powder diffraction (XRD), Raman, UV-Vis and Electron-paramagnetic resonance (EPR) spectroscopies. EPR spectra of ZP-50 and ZP-100 nanocomposites showed the presence of intensive peak at the g-values comparable to that for free electrons (2.0023) indicating the presence of oligo/poly (semiquinone radical cations), i.e. polarons as charge carriers in PANI part; ZP-150 showed weak polaron peak of PANI, and peak that can be assigned to defects in zirconia matrix (Zr3+, oxygen vacancies). The monoclinic crystal structure of ZrO2 nanoparticles in all nanocomposites was confirmed by XRD and by Raman spectroscopy. The photocatalytic activities of ZP nanocomposites were evaluated using the photocatalytic degradation of trichlorophenol (TCP) and Rhodamine B model compounds and compared with the activity of bare ZrO2 nanoparticles. Enhanced degradation efficiencies of nanocomposites regarding TCP degradation were observed. (C) 2017 Elsevier B.V. All rights reserved.

Solvothermal synthesis of ZrO2-TiO2 binary oxides and pure counterparts at 150 degrees C in water/isopropanol media is presented. Titanium (IV) isopropoxide and zirconium (IV) propoxide were used as precursors. XRD and TEM techniques were used for structural and morphological characterization of obtained samples. XPS spectra of mixed oxide samples were compared in order to correlate composition of samples with surface properties and presence of defects. Relative positions of defect states within band-gaps of semiconductors were estimated from UCPL spectra. UV-Vis DRS spectra revealed that both pure oxides experienced red shift of absorption thresholds compared to reference data. Photocatalytic activities of all samples were probed under simulated Solar light on three model compounds: phenol, 4-chlorophenol (4-CP) and 2, 4, 6-trichlorphenol (TCP). Pure TiO2 showed the highest photocatalytic activity in the case of phenol. However, pure ZrO2 and binary oxides showed higher photoactivity in degradation of 4-CP and TCP. The activity of wide band-gap semiconductors under simulated Solar light in photodegradation of phenol and its derivatives is most probably the consequence of formation of charge transfer complexes between pollutant molecules and semiconductors surface.

The aim of this study was to develop simple and efficient method for immobilization of Candida antarctica lipase B onto hydrophobic anion exchange resin Purolite(A (R)) MN102 and to apply immobilized catalyst for the enzymatic synthesis of two valuable esters-isoamyl acetate and l-ascorbyl oleate. At optimized conditions (1 M phosphate buffer pH = 7, 7 h at 25 A degrees C, and 18.75 mg of offered proteins g(-1) of support), immobilized lipase with hydrolytic activity of 888.4 p-nitrophenyl butyrate units g(-1) was obtained. Afterwards, preparation was applied for the solvent-free synthesis of isoamyl acetate from triacetin and isoamyl alcohol. At 75 A degrees C, 1 M of isoamyl alcohol, and 6 mg ml(-1) of enzyme 100 % yield was achieved in 6 h, while at prolonged reaction times, complete conversion was enabled even at lower temperatures, lower lipase loadings, and higher substrate concentrations. After 15 consecutive reuses (60 h), activity of catalyst dropped to 50 % of its initial value and total amount of 1.31 mol (170.55 g) of ester with 1 g of biocatalyst was produced. Even higher operational stability of lipase (25 % loss of activity in 200 h) was observed in the synthesis of l-ascorbyl oleate performed in organic solvent (t-butanol). Multiple use of one batch of immobilized biocatalyst in both cases led to a significant process cost reduction and substantial increment of corresponding productivities.

L-Ascorbyl oleate is recognized as efficient liposoluble antioxidant and biosurfactant which can be synthesized by using immobilized lipases as catalysts in organic media. However, development of economical production process is still a challenge, particularly in (semi)continuous systems. Hereby, we present application of novel immobilized lipase preparation, lipase B from Candida antarctica hydrophobically adsorbed onto styrene divinylbenzene based support, for the synthesis of L-ascorbyl oleate in batch bioreactor (BB) and fluidized bed bioreactor (FBB) with recirculation of reaction medium. Reaction kinetics was described by Ping Pong bi bi mechanism with low acyl donor inhibition. Considerably higher reaction rates (similar to 40%) were accomplished in FBB. Hydrodynamic study revealed that reaction is kinetically controlled and unhindered external and internal mass transfer was enabled in both systems. However, much higher shear stress occurred in BB (10.46 Pa) comparing to FBB (5 x 10(-2) Pa). After 12 consecutive reaction cycles lasting 24h, 23.13 g of product per gram of biocatalyst was synthesized in a FBB. Within this study, usage of new immobilized enzyme in semicontinuous system enabled high reaction rates and satisfying operational stability in the synthesis of L-ascorbyl oleate, offering good prospect for further process development.

The agricultural raw industry generates large amounts of annually by-products that create disposal problems. Hitherto, there have been no reported papers about the simultaneous production of cellulase and beta-amylase from these raw materials using Paenibacillus sp. that would reduce the costs. Thus, in this paper simultaneous cellulase (CMC-ase and avicelase) and beta-amylase production using barley bran and the application of the natural isolate Paenibacillus chitinolyticus CKS1 and potential enzymes in the hydrolysis process was studied. Response surface methodology was used to obtain the maximum enzyme activity (CMC-ase 0.405 U mL(-1), avicelase 0.433 U mL(-1) and beta-amylase 1.594U mL(-1)). Scanning electron microscopy showed degradation of the lignocellulosic-starch structure of barley bran after fermentation. The CKS1 bacterial supernatant, which contains cellulases and beta-amylase, could hydrolyze cotton fibres and barley bran, respectively. The main products after enzymatic hydrolysis of cotton fibres and barley bran, glucose (0.117 (-1)(g gmat)) and maltose (0.347 (-1)(g gmat)), were quantified by high performance liquid chromatography (HPLC). The produced enzymes could be used for hydrolysis of cotton fabric and barley bran to glucose and maltose, respectively. Application of simultaneous enzymes production using an agricultural by-product is economically and environmentally accepted and moreover, valuable biotechnological products, such as glucose and maltose, were obtained in this investigation.

In this study, the nanocomposites based on semiconductor lead sulfide (PbS) nanoparticles and poly (vinyl alcohol) (PVA) were investigated. The gamma irradiation induced in situ incorporation of PbS nanoparticles in crosslinked polymer network i.e. PVA hydrogel was performed. PVA hydrogel was previously obtained also under the influence of gamma irradiation. UV Vis absorption and X-ray diffraction measurements were employed to investigate optical and structural properties of PbS nano particles, respectively, and obtained results indicates the presence of nanoparticles with approximately 6 nm in diameter and face centered cubic rock-salt crystal structure. The porous morphology was confirmed by scanning electron microscopy. Swelling data revealed that investigated hydrogels (PVA and PbS-PVA nanocomposite) shows non-Fickian diffusion, indicating that both diffusion and polymer relaxation processes controlled the fluid transport. The values of diffusion coefficients have an order of magnitude 10(-9) cm(2)/s (typical values for water diffusion in polymers) and the best fit with the experimental results showed the Etters approximation. Comparing the thermal properties of PbS-PVA xerogel nanocomposite with PVA xerogel it was observed that incorporation of PbS nanoparticles in crosslinked PVA matrix just slightly enhanced the thermal stability of nanocomposite. (C) 2016 Elsevier Ltd. All rights reserved.

Hot-injection method for synthesis of ZnIn2S4 (ZIS) in organic media was studied. Nanosized ZnIn2S4 is successfully synthesized in oleic acid/oleylamine mixture in different ratios, which are both: complexing and/or capping agents. Nanosheets/nanoscrolls of about 50 nm are obtained. The band gaps of synthesized nanostructures were calculated to be in the range from 2.6 to 3.0 eV, values which are increased compared to bulk value (2.3-2.5 eV). The increase of band gap can be assigned to nanodimensions of the particles. Potential of band edges is calculated using empirical equation and find to be in the range from -0.16 to -0.36 V for conduction band, and from 2.24 to 2.69 V for valence band. By using XRD and TEM techniques, crystal structure and morphology of obtained materials were investigated, and detailed formation and growth mechanism of nanosheets/nanoscroles is proposed accordingly. (C) 2016 Elsevier Ltd. All rights reserved.