Modification Of ZnO Research Articles

Deposition of Sol-Gel ZnO:Mg Films and Investigation of Their Structural and Optical Properties.

This work presents a facile sol-gel method for the deposition of ZnO and ZnO:Mg films. The films are spin coated on silicon and quartz substrates. The impact of magnesium concentrations (0, 0.5, 1, 2 and 3 wt%) and post-annealing treatments (300-600 °C) on the film's structural, vibrational and optical properties is investigated. Undoped ZnO films crystallize in the wurtzite phase, with crystallite sizes ranging from 9.1 nm (300 °C) to 29.7 nm (600 °C). Mg doping deteriorates the film crystallization and shifting of 002 peak towards higher diffraction angles is observed, indicating the successful incorporation of Mg into the ZnO matrix. ZnO:Mg films (2 wt%) possess the smallest crystallite size, ranging from 6.2 nm (300 °C) to 25.2 nm (600 °C). The highest Mg concentration (3 wt%) results into a segregation of the MgO phase. Lattice constants, texture coefficients and Zn-O bond lengths are discussed. The diminution of the c lattice parameter is related to the replacement of Zn2+ by Mg2+ in the ZnO host lattice. The vibrational properties are studied by Fourier transform infrared (FTIR) spectroscopy. IR lines related to Mg-O bonds are found for ZnO:Mg films with dopant concentrations of 2 and 3 wt%. The optical characterization showed that the transmittance of ZnO:Mg thin films increased from 74.5% (undoped ZnO) to about 89.1% and the optical band gap energy from 3.24 to 3.56 eV. Mg doping leads to a higher refractive index compared to undoped ZnO films. The FESEM (field emission scanning electron microscopy) technique is used for observation of the surface morphology modification of ZnO:Mg films. The doped ZnO films possess a smoother grained surface structure, opposite to the wrinkle-type morphology of undoped sol-gel ZnO films. The smoother surface leads to improved transparency of ZnO:Mg films.

Electronic control of catalytic activity of ZnO for higher alcohols synthesis via tailoring Fermi level

Metal doping are essential for electronic modulation of semiconductors, leading to different Fermi level, which determined the surface chemisorption and catalytic properties. Here, ZnO doping with 4 mol% Cu were synthesized by four preparation routes, which tuned Cu existing states and Fermi level appearing remarkable impacts on the catalytic performance of catalysts. It shows a negative correlation between synthesis of higher alcohols and Fermi level over electronically modified ZnO catalysts, and the lower Fermi level exerted better facilitation for the carbon chain growth. Copper was incorporated into ZnO lattice and existed in the form of isolated Cu2+, which regulated the electronic structure of ZnO with lower Fermi level and boosted the process of catalysts obtaining electrons. Thus, the lower Fermi level promoted the dissociation CO bond and p-type reaction of forming surface alkyl species, and a higher proportion of straight chain higher alcohols can be achieved via CO or CHxO* inserting into alkyl species. Especially the catalyst prepared by urea hydrolysis with the lowest Fermi level significantly increased the higher alcohols fraction in total alcohol products to 69.9%. For comparison, the higher Fermi level are unfavorable for p-type reaction, leading to high methanol selectivity. This work provides a new viewpoint for promoting catalytic performance from the perspective of electronic modification of ZnO.

Oxygen vacancy modification of commercial ZnO by hydrogen reduction for the removal of thiabendazole: Characterization and kinetic study

The effect of temperature-programmed H2 reduction on modification of surface oxygen vacancies in commercial ZnO (C-ZnO) is investigated. The photocatalytic degradation of the fungicide thiabendazole was optimized by treating C-ZnO with 10% H2/Ar gas at 500 °C over 5 h. The formation of oxygen vacancies and their catalytic activity were compared before and after the reduction treatment based on their characterization analysis (e.g., TPR, FE-SEM, EDS, XPS, Tauc plot, XRD, and BET). Our most recent kinetic modeling was carried out on the experiments using C-ZnO and T500 at different pH values. The highest adsorption removal and photocatalytic degradation rate (and quantum yield) was occurred at pH 3 and 11, respectively. Good reusability of the optimal reduced catalyst was confirmed when tested over five cycles. A strong compatibility between the kinetic modeling results and all characterization analyses supports the potent role of reduction treatment for the modification of oxygen vacancies on photocatalysis.

Construction of high-performance ZnO/C/Bi<sub>2</sub>O<sub>3</sub> composites and their application in NiZn battery

<p indent="0mm">The zinc anode easily encounters some problems such as dendrite growth, shape change, and hydrogen evolution during the charge-discharge process, which lead to the poor cycle life of NiZn battery. To solve these problems, a novel method for surface modification of ZnO was proposed. By using PVA as carbon source, ZnO/C composite was first synthesized; and then, ZnO/C/NH₄Bi₃F₁₀ composite was prepared in the ethylene glycol; ZnO/C/ NH₄Bi₃F₁₀ finally transformed into ZnO/C/Bi₂O₃ after being calcined at high temperature. X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HRTEM) and elemental distribution mapping results confirmed the successful synthesis of ZnO/C/Bi₂O₃ composites. The formation mechanism of the composites was discussed in detail. Cyclic voltammetry (CV), electrochemical impedance spectrosocopy (EIS) and constant current charge-discharge tests showed that ZnO/C/Bi₂O₃ composite with the Bi₂O₃ content of 2% displayed the highest electrochemical activity. Furthermore, the NiZn battery assembled from the composite with 2 wt% Bi₂O₃ displayed a cycle life up to 1806 times with the highest energy density of 166.5 Wh kg⁻¹. The energy density of 164.44 Wh kg⁻¹ and Coulombic efficiency of 90% were still maintained after 1806 cycles. The as-prepared ZnO/C/Bi₂O₃ composites exhibit excellent electrochemical performance and great potential for practical applications. This innovative synthesis method is hopeful to be extended to prepare other composites.

ZnO under Pressure: From Nanoparticles to Single Crystals

In the present review, new approaches for the stabilization of metastable phases of zinc oxide and the growth of ZnO single crystals under high pressures and high temperatures are considered. The problems of the stabilization of the cubic modification of ZnO as well as solid solutions on its basis are discussed. A thermodynamic approach to the description of zinc oxide melting at high pressures is described which opens up new possibilities for the growth of both undoped and doped (for example, with elements of group V) single crystals of zinc oxide. The possibilities of using high pressure to vary phase and elemental composition in order to create ZnO-based materials are demonstrated.

Preparation and absorbing property analysis of ZnO-doped magnetic graphene composite material

The ZnO-doped magnetic graphene composite materials were prepared by a two-step hydrothermal method. The microstructures and compositions were characterized by scanning electron microscope, transmission electron microscope, X-ray diffractometer, and X-ray photoelectron spectroscopy. The electromagnetic properties were determined by vector network analyzer and vibrating sample magnetometer. The strengthening mechanism of absorbing properties was analyzed in combination with first-principles calculations. The results show that the ZnO sheets and Fe3O4 balls closely overlap under the ball-sheet and ball-ball interactions and form abundant micro-interfaces and cavity structures, enhancing the microwave absorbing property. The composite absorbing material reaches the minimum reflection loss of − 53.96 dB at 8.96 GHz with a thickness of 1.81 mm, and the effective absorbing band could be tun-able flexibly within the range of 5.2 ∼ 18 GHz by adjusting the matching thickness within the range of 0.84 ∼ 3.03 mm. First-principles calculations further demonstrate that the modification of ZnO greatly changes the electronic state and structure, reduces the energy barrier of electrons transferring, forms special charge transferring channels, increases the concentration of carriers, and improves the absorbing capacity of the material.

A mini-review on rare earth metal doped ZnO nanomaterials for photocatalytic remediation of waste water

The mineralization and degradation of organic compounds present in waste water by heterogeneous photocatalysis has gained wide attention due to its effectiveness and tenancy to utilize UV-Visible solar light spectrum. The chemical stability, non-toxic character, magnificent electrical and optical properties have been recognized the ZnO as useful material for waste water treatment in environmental remediation technology. However, photocatalytic activity of ZnO limited to ultraviolet region because of its wide band gap (3.37eV). ZnO wide band gap obstruct photo-excitation for actual photocatalytic applications under abundant, safe and clean solar energy source. Many methods have been evolved in last decades to overcome this barrier. ZnO surfaces have been tailored with rare-earth metals to enhance its optical, surface and photocatalytic properties by different research groups. The doping with rare-earth metal ions enhanced the efficiency of ZnO photocatalyst by reducing band gap and shifted the absorbed wavelength to the visible region. This review paper compiles the attempts on modification of ZnO and their effect on photocatalytic activities by using rare earth metals.

The surface modification of spherical ZnO with Ag nanoparticles: A novel agent, biogenic synthesis, catalytic and antibacterial activities

Nowadays, the industrial wastewater pollutants including toxic dyes and pathogenic microbes have caused serious environmental contaminations and human health problems. In the present study, eco-friendly and facile green synthesis of Ag modified ZnO nanoparticles (ZnO-Ag NPs) using Crataegus monogyna ( C. monogyna ) extract (ZnO-Ag@CME NPs) is reported. The morphology and structure of the as-biosynthesized product were characterized by field emission scanning electron microscopy (FESEM), X-Ray diffraction (XRD), differential reflectance spectroscopy (DRS), dynamic light scattering (DLS), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FT-IR), and energy-dispersive X-ray spectroscopy (EDS) techniques. TEM and FESEM images confirmed the oval and spherical-like structure of the products with a size of 55–70 nm. The EDS analysis confirmed the presence of Zn, Ag, and O elements in the biosynthesized product. The photocatalytic results showed ZnO-Ag@CME NPs were degraded (89.8% and 75.3%) and (94.2% and 84.7%) of methyl orange (MO) and basic violet 10 (BV10), under UV and sunlight irradiations, respectively. The Ag modified ZnO nanoparticles exhibited enhanced catalytic activity towards organic pollutants, and showed better performance than the pure ZnO nanoparticles under UV and sunlight irradiations. This performance was probably due to the presence of silver nanoparticles as a plasmonic material. Antibacterial activity was performed against different bacteria. ZnO-Ag@CME NPs showed high antibacterial activity against K. pneumoniae, S. typhimurium, P. vulgaris, S. mitis, and S. faecalis with MIC values of 50, 12.5, 12.5, 12.5, and 12.45 µg/mL, respectively. All in all, the present investigation suggests a promising method to achieve high-efficiency antibacterial and catalytic performance.

Eco-friendly synthesis of self-reporting robust superhydrophobic coatings with damage sensitive photoluminescence

Polymer-based superhydrophobic coatings have attracted tremendous attention as promising multi-functional materials. Nevertheless, the practical applications of superhydrophobic coatings are seriously restricted by the well-known drawbacks of the pollution-carrying fabrication methods (e.g., harmful fluorinated compounds and organic solvents employed) and the fragile mechanical durability. Meanwhile, the absence of the smart response to external stimulus is another restricted factor for application as a promising smart multifunctional material. It is highly challenging to synthesize desirable self-reporting robust superhydrophobic coatings for autonomously indicating internal damages or failure development in early stages with the eco-friendly method. In this paper, the self-reporting robust superhydrophobic coatings with damage-sensitive photoluminescence (PL) were prepared by the facile, non-fluorinated, and eco-friendly method. Both the surface superhydrophobic modification of tetrapod-shaped ZnO (T-ZnO) and preparation of superhydrophobic coating were implemented with the waterborne formula. Benefited from the isotropic co-crosslinked interlocking networks constructed by covalent bonding the methacrylate copolymers onto the surface of T-ZnO and crosslinked with the methacrylate copolymers matrix, the as-prepared superhydrophobic coating showed excellent mechanical durability. The coating can still maintain high water-repellent (Contact angle (CA) = 150°) after 1000 cycles of severe mechanical abrasion. More importantly, the as-prepared superhydrophobic coating exhibited a significant PL response to the damage-related structural changes under mechanical abrasion. Furthermore, the anti-corrosion and self-cleaning properties of the as-prepared superhydrophobic coating were also evaluated. Under the merits in the synthesis method and the damage-related PL characteristics, the as-prepared superhydrophobic coating has a promising application in non-destructive detection and opens up the new possible application in engineering scopes.

Surface modification of ZnO on the Zn-polar 0001 face by self-assembled triptycene-based polar molecules along with an increase of electric conductance

The application of self-assembled monolayers (SAMs) is a representative method of surface modification for tuning material properties. In this study, we examine the influence of the surface modification by coating the Zn-polar 0001 surface of ZnO single crystal with a SAM of triptycene-based polar molecules in our own technique and investigated temperature dependences of the sheet conductance of the surface with and without the SAM. The sheet conductance at 70 K with the SAM is increased by an order of magnitude, compared to the case without the SAM. We infer that the additional electrons are introduced at the surface by the polar triptycene molecules, whose electropositive hydroxyl groups are supposed to face toward the Zn-polar surface of ZnO. The present result implies that the molecular orientation of the triptycene SAM plays a critical role in the surface properties of oxide semiconductors.

Fabrication of In2O3 functionalized ZnO based nanoheterojunction photoanode for improved DSSC performance through effective interfacial charge carrier separation

This report is to address the limitation of conventional dye-sensitized solar cells (DSSCs) designed using pristine ZnO and N719 dye, which suffers from low performance due to the high charge carrier recombination and the formation of Zn2+-N719 complex over the surface of photoanode. Here we demonstrate the fabrication of ZnO–In2O3 heterojunction based photoanode to extend the charge carrier lifetime by effective interfacial transfer and to boost the light harvesting capacity in dye sensitized solar cells. This opted strategy also helps to prevent the formation dye complex over the photoanode surface. As a result, ZnO–In2O3 heterojunction with optimal composite ratio (1:1) could show better DSSC performance compared to remaining samples when applied as photoanode. Optical analyses and impedance measurements confirmed the enhanced visible light absorption and reduced charge transfer resistance of the composite photoanode due to the modification of ZnO using In2O3 as a counterpart. The results showed that the optimally designed photoanode with superior charge carrier life time and low charge transfer resistance exhibits power conversion efficiency (PCE) of 1.22%, which is nearly 4 times than the pristine ZnO.

Modification of SiO2, ZnO, Fe2O3 and TiN Films by Electronic Excitation under High Energy Ion Impact

It has been known that the modification of non-metallic solid materials (oxides, nitrides, etc.), e.g., the formation of tracks, sputtering representing atomic displacement near the surface and lattice disordering are induced by electronic excitation under high-energy ion impact. We have investigated lattice disordering by the X-ray diffraction (XRD) of SiO2, ZnO, Fe2O3 and TiN films and have also measured the sputtering yields of TiN for a comparison of lattice disordering with sputtering. We find that both the degradation of the XRD intensity per unit ion fluence and the sputtering yields follow the power-law of the electronic stopping power and that these exponents are larger than unity. The exponents for the XRD degradation and sputtering are found to be comparable. These results imply that similar mechanisms are responsible for the lattice disordering and electronic sputtering. A mechanism of electron–lattice coupling, i.e., the energy transfer from the electronic system into the lattice, is discussed based on a crude estimation of atomic displacement due to Coulomb repulsion during the short neutralization time (~fs) in the ionized region. The bandgap scheme or exciton model is examined.

ZnO/Ag3PO4 and ZnO–Malachite as Effective Photocatalysts for the Removal of Enteropathogenic Bacteria, Dyestuffs, and Heavy Metals from Municipal and Industrial Wastewater

Different composites based on ZnO/Ag3PO4 and ZnO–malachite (Cu2(OH)2CO3) were synthesized in order to determine their effectiveness in the treatment of municipal and industrial wastewaters (mainly polluted by enteropathogenic bacteria, dyes, and heavy metals). The addition of Ag3PO4 and malachite did not significantly modify the physicochemical properties of ZnO; however, the optical properties of this oxide were modified as a result of its coupling with the modifiers. The modification of ZnO led to an improvement in its effectiveness in the treatment of municipal and industrial wastewater. In general, the amount of malachite or silver phosphate and the effluent to be treated were the determining factors in the effectiveness of the wastewater treatment. The highest degree of elimination of bacteria from municipal wastewater and discoloration of textile staining wastewater were achieved by using ZnO/Ag3PO4 (5%), but an increase in the phosphate content had a detrimental effect on the treatment. Likewise, the highest Fe and Cu photoreduction from coal mining wastewater was observed by using ZnO–malachite (2.5%) and ZnO/Ag3PO4 (10%), respectively. Some of the results of this work were presented at the fourth Congreso Colombiano de Procesos Avanzados de Oxidación (4CCPAOx).

Enhancing the Schottky-barrier height by inserting a thin MgO layer between Au and annealed-ZnO

The effects of a thin MgO insertion layer between Au and annealed-ZnO on the Schottky-barrier diodes (SBDs) of Au/annealed-ZnO were studied. The structure of Au/as-deposited ZnO (SBD_A) presents a rather leaky (near ohmic) characteristic owing to the presence of oxygen vacancies on the ZnO surface. After post-annealing of ZnO in air, the Au/annealed-ZnO (SBD_B) exhibits a rectifying behavior as a result of the compensated oxygen vacancies. Upon inserting a MgO film between the Au and annealed-ZnO, the leakage current is significantly reduced by approximately 3-orders of magnitude in the Au/MgO/annealed-ZnO structure (SBD_C), largely enhancing the rectification ratio from 10.3 to 731. This is because the oxygen vacancies are further reduced by the MgO modification of ZnO. The post-ZnO annealing and MgO insertion increased the Schottky-barrier height (SBH) from 0.58 to 0.68 and 1.1 eV in SBD_A, SBD_B, and SBD_C, respectively. Hence, the MgO insertion not only decreases the oxygen vacancies on the ZnO surface, it also increases the SBH. X-ray diffraction, X-ray photoelectron spectroscopy, and band-diagrams were employed to elucidate the mechanisms of the increase in SBH.

Novel starch-mediated synthesis of Au/ZnO nanocrystals and their photocatalytic properties

A novel solution–solid synthesis method for preparation of ZnO and Au/ZnO composite nanocrystals using starch matrix has been developed and optimized. The process is characterized by simplicity, environmental compatibility and good performance. Nanocomposite samples with different gold content have been synthesized and studied with respect to their structure, size and shape of nanocrystals, thermal behavior, surface characteristics and optical properties, as well as their photocatalytic activity. We have found that modification of nanocrystalline ZnO with gold nanocrystals strongly influences the porosity of nanocomposites - less micro- and mesopores are formed, which results in a reduced specific surface area. The synthesized ZnO and Au/ZnO nanocrystals are active photocatalysts for the photocatalytic degradation of methylene blue (MB), as a model pollutant dye, in the UV region. There is a decrease in photocatalytic activity with an increase of the gold content in the nanocomposite photocatalyst. The degree of MB degradation obtained with a pure ZnO sample is comparable to that with the Au/ZnO photocatalyst with the lowest gold content 0.05 at. %. New and interesting result has been obtained relating to maximum specific (intrinsic) photocatalytic activity of 0.05 at. % Au/ZnO nanocrystals.

Modification of ZnO nanoparticles with silanes enables their application as anticancer agents

Introduction Nanoparticles (NPs) are a wide class of materials that include particulate substances sized less than 100 nm. Inorganic ZnO NPs have found applications in several industrial fields such as the optical, electronic, pharmaceutical and cosmetics [1]. However, in many specific fields the applications are limited, since the particles tend to aggregate/agglomerate due to the hydrophilic nature of the surface. For potential clinical applications, surface modification of ZnO plays a crucial role in the biocompatibility of ZnO NPs [2]. Using organosilane modifying agents, improved hydrophobicity of the resulting ZnO NPs, induced by the non-polar terminal groups, can be achieved, and thus, very small and highly dispersed particles can be obtained. ZnO silanes were found to have antibacterial activity against several pathogens [3]. The NP size highly influenced the antibacterial activity, which increase with decreasing size. The ZnO NPs may induce bacterial cell membrane damage, resulting in bacterial cell death. Motivated by these findings and others reporting anticancer activity for pristine ZnO NPs [4], the aim of this study was to investigate the anticancer activity and mechanism of cell death of silane-modified ZnO nanoparticles against A2780 ovarian cancer cells and evaluate if for the cancer cells a correlation between size and activity was also observed. Materials and Mmethods The silane modified ZnO NPs were prepared by the addition of (3-glycidyloxypropyl) trimethoxysilane (GPTMS) as a surface modifier at 0% (G0) and 10% (G3) molar ratio of Si/Zn. The obtained NPs were characterised by high resolution transmission electron microscopy (HRTEM), X-ray diffraction and UV-Vis spectrometry. The cytotoxic activity in ovarian cancer cells were assessed by the MTT colorimetric assay. The morphological cellular alterations were visualised by electron microscopy (TEM). Results The silane modified ZnO NPs exhibited significant cytotoxic activity against A2780 ovarian cancer cells. The NP size, ca. 13 nm for G0 and ca. 3 nm for G3, highly influenced the cytotoxic activity, which increased with decreasing particle size, IC50: ∼100 µg/mL(G0) and ∼30 µg/mL(G3). The ZnO silanes affected the cellular integrity by the induction of organelle damage evidenced by TEM. Discussion and conclusions Although preliminary, results indicate that ZnO silanes are interesting platforms to explore as anticancer agents. Studies on the ultrastructural level (TEM/SEM) are needed to understand their cytotoxic mechanism and to give clues on their potential targets.

Photo-assisted inactivation of highly drug resistant bacteria and DPPH scavenging activities of zinc oxide graphted Pd-MCM-41 synthesized by new hydrothermal method

A major current biomedical challenge is to find materials that are specific, have high efficiency and with long lasting stability to serve as antimicrobial agents. In this contribution we examined new bifunctional nanostructural materials (ZnO/Pd-MCM-41) which were synthesized by a new hydrothermal procedure. To deposit active cites i.e. ZnO, a new protocol was followed in which catechol was used as a precipitating agent. Results indicated that nanostructures comprising palladium nanocrystals of a small size dispersed consistently within the hexagonal pores of the MCM-41 and also ZnO was successfully coated on mesoporous Pd-MCM-41 and that the mesoporous Pd-MCM-41 structure has been well-maintained upon modification of ZnO. The ZnO/Pd-MCM-41 is promising antibacterial agent and have efficient light inhibition activity towards Escherichia coli (E. coli), Psedomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus). The inhibition zone of irradiated ZnO/Pd-MCM-41 nanostructure against E. coli, P. aeruginosa and S. aureus were (17 ± 0.4) mm, 18 (±0.4) mm and 22 (±0.2) mm respectively while that in dark were (9 ± 0.5) mm, 11 (±0.3) mm and 13 (±0.4) mm respectively. The production of reactive oxygen species and hemolytic assay were also analyzed. Different parameters affecting the photo-inhibition efficiency of ZnO/Pd-MCM-41 were also studied. Likewise, the antioxidant activity of these nanostructures was studied against DPPH stabilization. Results indicated that the synthesized nanostructures are highly active and stabilized 99 % DPPH at very low concentration i.e. 1.4 mg/mL.

Rational surface modification of ZnO with siloxane polymers for room-temperature-operated thin-film transistor-based gas sensors

High demands for and rapid development of technologies related to the Internet of Things (IoT) call for a pertinent technological breakthrough in sensing devices to effectively detect various external stimuli or target analytes. Advanced sensing platforms utilizing thin-film transistors (TFTs) are essential for realizing cost-effective and high-performance chemical sensors. Here, it is reported that the utilization of a gas-selective layer based on polymeric chromatographic stationary phases is an unprecedented and facile method to establish simultaneously the desired gas selectivity and responsivity of ZnO thin films at room temperature. With the aid of computational studies, in-depth analysis and comparison of gas-sensing and the charge transfer mechanism between the gas and the resulting sensor devices are performed. ZnO with cyanopropylmethyl-phenylmethyl polysiloxane films provide excellent selective sensing with gas mixtures, and the achieved response to vaporized ethanol is nearly three times higher than the response of pristine ZnO at ~22 °C and atmospheric pressure. This effective enhancement of sensing performance under ambient conditions is attained through the transition from chemisorption to physisorption based on intermolecular interactions between gas molecules and gas-selective polymers. This work demonstrates a potent yet cost-effective method to fabricate low power consumption gas sensor systems based on metal oxide TFT.

Two-Phase Synthesis in n-Hexane–Water, Characterization, and Photocatalytic Activity of ZnO/Bi2Sn2O7 Nanocomposite

The synthesis, characterization, and photocatalytic activity of ZnO/Bi2Sn2O7 nanocomposite are reported herein. ZnO/Bi2Sn2O7 was synthesized using a green high-speed stirring (HSS)-assisted method in the n-hexane–water system using Cassia alata leaf extract (CLE). ZnO/Bi2Sn2O7 nanocomposite formed at the interface between n-hexane and water owing to the essential role of CLE secondary metabolites. Various analytical techniques were applied to characterize the optical, structural, and morphological properties as well as particle size of the nanocomposite. The ZnO/Bi2Sn2O7 nanocomposite with average particle size of 9.8 nm exhibited efficiency of 86.59% for degradation of rhodamine B within 120 min. This high visible-light-driven photocatalytic activity was obtained by modification of ZnO with Bi2Sn2O7, resulting in a decrease of the bandgap energy from 3.12 eV to 2.80 eV. This research offers a novel method for efficient synthesis of nanocomposites with high photocatalytic activity.

The New Pharmaceutical Compositions of Zinc Oxide Nanoparticles and Triterpenoids for the Burn Treatment.

We studied oleogels containing zinc oxide nanoparticles (ZnO NPs) and lupane triterpenoids in sunflower oil for the treatment of burns. The modification of ZnO was carried out by treatment with alcohol solutions of betulin, betulonic acid, betulin diacetate and betulin diphosphate. The properties of modified ZnO NPs were studied by powder XRD (average sizes of 10–20 nm), FTIR (νZnO 450 cm−1), UV–vis (345–360 nm), and blue–violet emission (380–420 nm). The identification and assay of modified ZnO NPs and triterpenoids were estimated. The treatment by oleogels of deep II-degree burns was studied on rats using histological studies, Doppler flowmetry and evaluation of enzymes activity and malonic dialdehyde (MDA) level. After the action of oleogels, burn wound area, and the necrosis decreased twice on the 10th day in comparison with the 1st day after burn. The microcirculation index in the near-wound zone by 20–30% improved compared with the group without treatment. Evaluation of the enzyme activity and the MDA level after treatment by oleogels during the course of 10 days showed them returning to normal. The improvement of antioxidant biochemical indexes, as well as wounds’ healing, was mainly determined by the influence of zinc oxide nanoparticles.