Zinc Oxide Precursor Research Articles

Polymer precursor method for the synthesis of zinc oxide nanoparticles: A novel approach

This study presents a novel approach to synthesize zinc oxide (ZnO) nanoparticles using a polymer precursor method, offering precise control over particle size in the nanometer scale. Zinc oxide nanoparticles are of significant interest due to their wide-ranging applications in various fields such as solar cells, gas sensors, photocatalysts, and nanomedicines. The synthesized nanoparticles were thoroughly characterized using X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Fourier Transform Infrared spectroscopy (FTIR). The distinct hexagonal form detected in the XRD pattern, featuring characteristic reflection planes at angles of 31.72° (100), 34.39° (002), 36.23° (101), and 47.44° (102), signifies the synthesis of ZnO possessing a hexagonal wurtzite structure. The SEM and TEM images revealed uniformly spherical particles with an average size ranging from 35 to 40 nm. Such uniform morphology and size distribution are critical for ensuring consistent performance in applications such as gas sensing and catalysis. Additionally, the FTIR spectra indicated a reduction in impurities after the synthesis process, highlighting the effectiveness of the polymer precursor method in producing high-quality ZnO nanoparticles. Heating the ZnO precursor material at 400°C for 2 hours significantly reduces impurities, suggesting conversion to ZnO nanoparticles.

Over 19% Efficient Inverted Organic Photovoltaics Featuring a Molecularly Doped Metal Oxide Electron-Transporting Layer.

Molecular doping is commonly utilized to tune the charge transport properties of organic semiconductors. However, applying this technique to electrically dope inorganic materials like metal oxide semiconductors is challenging due to the limited availability of molecules with suitable energy levels and processing characteristics. Herein, n-type doping of zinc oxide (ZnO) films is demonstrated using 1,3-dimethylimidazolium-2-carboxylate (CO2-DMI), a thermally activated organic n-type dopant. Adding CO2-DMI into the ZnO precursor solution and processing it atop a predeposited indium oxide (InOx) layer yield InOx/n-ZnO heterojunctions with increased electron field-effect mobility of 32.6 cm2 V-1 s-1 compared to 18.5 cm2 V-1 s-1 for the pristine InOx/ZnO bilayer. The improved electron transport originates from the ZnO's enhanced crystallinity, reduced hydroxyl concentrations, and fewer oxygen vacancy groups upon doping. Applying the optimally doped InOx/n-ZnO heterojunctions as the electron-transporting layers (ETLs) in organic photovoltaics (OPVs) yields cells with improved power conversion efficiency of 19.06%, up from 18.3% for devices with pristine ZnO, and 18.2% for devices featuring the undoped InOx/ZnO ETL. It is shown that the all-around improved OPV performance originates from synergistic effects associated with CO2-DMI doping of the thermally grown ZnO, highlighting its potential as an electronic dopant for ZnO and potentially other metal oxides.

Zinc oxide doped with graphene quantum dots as improved electron transport layers for planner perovskite solar cells

Zinc oxide (ZnO), a material with excellent electron mobility and a low-temperature requirement for production, is a promising option for use as an electron transport layer in perovskite solar cells (PSCs). However, it does have the drawback of having a low open-circuit voltage ([Formula: see text]). Herein, to increase the [Formula: see text] parameter of ZnO-based PSCs, graphene quantum dots (GQDs) are incorporated into the ZnO precursor and used as desirable ETL for PSCs. The presence of GQDs in ZnO ETL facilitated photo-electrons at the ETL/perovskite interface by reducing charge transfer resistance in this interface. Compared to the net ZnO-based PSCs, solar cells using GQD-doped ZnO as ETL have better stability, comparable [Formula: see text], higher [Formula: see text], and FF. The best GQD-doped-ZnO ETL-based PSCs recorded the highest power conversion efficiency of 20.23% with [Formula: see text] of 1.130[Formula: see text]V. Meanwhile, the boosted PCE of FAPbI3-based PSCs is achieved due to the improved perovskite crystal quality, the effective defect passivation effect of GQDs at ZnO/FAPbI3 interface, and the increased electrical conductivity of ZnO ETL. In addition, the GQD-doped ETL devices showed higher ambient air stability than the devices with net ZnO ETLs.

Green Synthesis, Characterization, and Photocatalytic Activity of Zinc Oxide Nanoparticles on Photodegradation of Naphthol Blue Black Dye

Zinc oxide (ZnO) nanoparticles have been successfully synthesized using water extract of red dragon fruit (Hylocereus polyrhizus) stem with zinc acetate dihydrate as a precursor of ZnO. Chemical compounds contained in the red dragon fruit stem extract, such as phenolics, terpenoids, and steroids, acted as reducing agents, stabilizers, and capping agents. The phase structure, crystallite size, functional groups, shape, and morphology of ZnO nanoparticles were determined by X-ray diffraction (XRD), Fourier Transform infrared (FT-IR) Spectroscopy, and Scanning Electron Microscopy-Energy Dispersive X-ray (SEM-EDX). The XRD pattern confirmed the crystallinity of synthesized zinc oxide was in the zincite (ZnO) phase with an average crystallite size of 79.09 nm. Spectroscopy FTIR analysis showed that the synthesized ZnO nanoparticles had characteristics similar to the ZnO standard/commercial. SEM-EDX analysis revealed that the synthesized ZnO nanoparticles were spherical, evenly distributed, and homogeneous particle size. The photocatalytic activity of synthesized ZnO nanoparticles was evaluated on the photodegradation of naphthol blue black (NBB) dye. The results showed that the synthesized ZnO nanoparticles have high photocatalytic activity that can degrade NBB dye up to 98.82%. This high photocatalytic activity was obtained at operating parameter conditions with the initial pH of NBB at 2, the dosage of ZnO nanoparticles at 250 mg, and the initial dye concentration at 10 ppm.

Study of Bi-functional Applications of ZnO Nanoparticles Synthesized via Sonochemical Route

The sonochemical synthesis involved the dispersion of zinc oxide (ZnO) precursor in a suitable solvent, followed by ultrasonic irradiation to induce chemical reactions and nucleation of ZnO nanoparticles. The resulting nanomaterials exhibited a uniform particle size distribution, which is crucial for their photocatalytic efficiency. ZnO nanoparticles with a uniform particle size of 25 nm were successfully synthesized using a sonochemical route and were employed for the degradation of direct green and fast orange dyes under UV light irradiation. The band gap of the ZnO nanoparticles was determined to be 3.35 eV, indicating its potential as a photocatalyst for dye degradation. The degradation efficiency of the dyes was evaluated by monitoring the change in their concentration over time. The ZnO nanoparticles demonstrated excellent photocatalytic activity, efficiently degrading both dyes within a relatively short duration. The electrochemical studies further confirmed the potential applicability of the synthesized ZnO nanoparticles in various electrochemical systems. The ZnO electrode that was produced could detect lead in an acidic solution. The ZnO electrode is a promising electrode material for making sensor applications because of its higher electrochemical behaviour. Overall, this research contributes to the development of efficient and environmentally friendly approaches for wastewater treatment and lead sensor.

Accessibility and Mechanical Stability of Nanoporous Zinc Oxide and Aluminum Oxide Coatings Synthesized via Infiltration of Polymer Templates.

The conformal nanoporous inorganic coatings with accessible pores that are stable under applied thermal and mechanical stresses represent an important class of materials used in the design of sensors, optical coatings, and biomedical systems. Here, we synthesize porous AlOx and ZnO coatings by the sequential infiltration synthesis (SIS) of two types of polymers that enable the design of porous conformal coatings-polymers of intrinsic microporosity (PIM) and block co-polymer (BCP) templates. Using quartz crystal microbalance (QCM), we show that alumina precursors infiltrate both polymer templates four times more efficiently than zinc oxide precursors. Using the quartz crystal microbalance (QCM) technique, we provide a comprehensive study on the room temperature accessibility to water and ethanol of pores in block copolymers (BCPs) and porous polymer templates using polystyrene-block-poly-4-vinyl pyridine (PS75-b-P4VP25) and polymers of intrinsic microporosity (PIM-1), polymer templates modified by swelling, and porous inorganic coatings such as AlOx and ZnO synthesized by SIS using such templates. Importantly, we demonstrate that no structural damage occurs in inorganic nanoporous AlOx and ZnO coatings synthesized via infiltration of the polymer templates during the water freezing/melting cycling tests, suggesting excellent mechanical stability of the coatings, even though the hardness of the inorganic nanoporous coating is affected by the polymer and precursor selections. We show that the hardness of the coatings is further improved by their annealing at 900 °C for 1 h, though for all the cases except ZnO obtained using the BCP template, this annealing has a negligible effect on the porosity of the material, as is confirmed by the consistency in the optical characteristics. These findings unravel new potential for the materials being used across various environment and temperature conditions.

A novel method to improve anti-aging properties of SBS modified bitumen by zinc oxide/expanded vermiculite composite: Influence of zinc oxide particle loadings

Styrene-butadiene-styrene copolymer modified bitumen (SBSMB) has been commonly used in pavement construction for its excellent performance. However, during construction and service life, SBSMB is inevitably subjected to thermal-oxidative or ultraviolet aging as a result of factors in the environment like heat, light and oxygen. This study investigated the effects of zinc oxide/expanded vermiculite composite (Z/E) on SBSMB, in particular the effects of Z/E with different zinc oxide (ZnO) particle loadings on SBSMB. And Z/E with different ZnO particle loadings were prepared and characterized by X-ray fluorescence spectrometer, field emission scanning electron microscope, UV–Visible spectrometer and Fourier transform infrared spectrometer tests. To age bitumen samples, thin film oven test, pressure aging vessel and ultraviolet aging tests were used. Eventually, the effects of Z/E with various ZnO particle loadings on the storage stability, physical, rheological and anti-aging properties of SBSMB were investigated. According to the results, Z/E with different ZnO particle loadings are successfully prepared. There are uniform ZnO particles on the surface of expanded vermiculite and ZnO particle loadings are increased with the concentration of the ZnO precursor solution. Furthermore, the high-temperature performance of SBSMB is enhanced, but the low-temperature performance is slightly affected by Z/E. Whatever the aging mode, the introduction of Z/E can obviously reduce the viscosity aging index, softening point increment, complex modulus aging index and increase phase angle aging index of SBSMB, demonstrating that the aging resistance of SBSMB are significantly enhanced. It was determined that SBSMB with 29.5 wt%Z/E had the best aging resistance.

Low-temperature detection of acetone gas using ZnO-TiO2 nanorod on tapered multimode fiber decorated with Au-Pd thin films

This paper presents the influence of titanium dioxide (TiO2) as a catalyst to the zinc oxide (ZnO) nanorods coated on the tapered MMF fiber utilized as a sensing layer for the detection of acetone gas at low temperatures. To enhance the sensitivity of the sensor ZnO-TiO2 nanorods were decorated with Au-Pd film. Hydrothermal method was used to synthesize the ZnO nanorods while TiO2 powder was incorporated by using a simple doping procedure during fabrication. The decoration of the Au-Pd thin films is integrated with the ZnO-TiO2 by using DC sputtering method. The ZnO doped with 15 mM TiO2 shows a strong and significant peak based on XRD analysis which can be indexed to the hexagonal phase of ZnO. A few globular structures of TiO2 were randomly distributed as observed by the SEM image. Four different fiber sensing layers were prepared with respect to 10 mM ZnO precursor; ZnO nanorods (ZN), ZnO nanorods decorated with Au-Pd thin films (ZNAP), ZnO-15 mM TiO2 nanorods (ZTN) and ZnO-15 mM TiO2 nanorods decorated with Au-Pd thin films (ZTNAP). The spectrometry setup was used to measure the response of the sensor toward different concentrations of acetone gas in terms of intensity with respect to its wavelength. Notable output intensity responses were observed for ZTNAP in terms of sensitivity and standard deviation towards various acetone concentrations while the repeatability curve showed a high response of acetone gas at 10,000 ppm. All experiments were performed at the low temperature of 87 °C.

Reactive inkjet printed zinc oxide film processing

Zinc Oxide (ZnO) is a material with decades of investigation, used in coatings, biochemistry, and electronics. The rise of additive manufacturing and printed electronics shows increased interest in ZnO as a feed material for inkjet printing of multifunctional devices. Within this study, a ZnO precursor, Zinc Acetylacetonate Dihydrate [Zn(AcAc)2], is formulated into a reactive inkjet-printable ink using Hansen Solubility Parameter (HSP), in which the precursor was estimated to possess the parameters (mPa−1/2) δD = 16.5, δP = 9.9, δD = 13.2, and an HSP radius r of 6.5. Processing conditions for the reaction of the precursor into ZnO (thermal, chemical, and UV-irradiative) are investigated to develop in-situ morphological control and tunability of ZnO films.

ZnS/Ag2S decorated PES membrane with efficient near-infrared response and enhanced photocatalysis for pollutants photodegradation on high-turbidity water

By the combination of photocatalysis with membrane separation technology, a concurrent strategy of near-infrared (NIR) photocatalytic degradation and flow-through filtration for the treatment of antibiotics and dye effluent are proposed. After the deposition of homogeneous polyether sulfone (PES) layer with zinc acetate seeds as zinc oxide (ZnO) precursor on PES substrate membrane fabricated by non-solvent induced phase separation (NIPs), a photocatalytic membrane comprising of zinc sulfide (ZnS), silver sulfide (Ag2S), and PES substrate (ZnS/Ag2S@PES) was fabricated using successive ion layer adsorption and reaction (SILAR) and ion exchange method based on the conversion of ZnO into ZnS. ZnS/Ag2S@PES photocatalytic membrane with UV–vis-NIR full-spectrum response ability due to the construction of p-Ag2S/n-ZnS heterojunction can fulfil high pollutant photodegradation efficiency (methylene blue (MB) ∼ 70 % & tetracycline (TC) ∼ 58 %) in dead-end filtration by single pass. By simply two successive repeating units in flow-through filtration, more than 95 % of photodegradation efficiency for MB and TC can be achieved. More importantly, under NIR irradiation by the penetration of high-turbidity media and real turbidity wastewater, 68 % and 72 % of MB photodegradation efficiency can be respectively reached by only one unit within 1 h, which is expected to achieve the catalytic degradation to high-turbidity real industrial wastewater.

Precursor mediated and defect engineered ZnO nanostructures using thermal chemical vapor deposition for green light emission

We used thermal chemical vapour deposition to synthesize zinc oxide nanostructured thin films on n-type silicon substrate using zinc oxide (ZnO) and zinc chloride (ZnCl2) powder precursors in conjunction with bulk graphite powder. The synthesized ZnO nanostructured thin films structures are polycrystalline with a relatively enhanced c-axis orientation for ZnO powder precursor with respect to that of ZnCl2 precursor. The scanning electron microscopic analysis substantiate the higher c-axis orientation of ZnO nanostructures, grown using ZnO powder precursor. The photoluminescence (PL) and UV–Vis measurements suggest the presence of zinc vacancies, causing the green emission from both nanostructured thin films. The measured bandgap of ZnO nanostructured thin film using ZnO powder precursor is slightly higher than that of ZnCl2 powder precursor. The capacitance-voltage and Mott-Schottky measurements showed the n-type characteristics with 6.3 × 1016 cm−3 and 2.7 × 1015 cm−3 carrier densities for ZnO nanostructured thin films prepared using ZnO and ZnCl2 precursors, respectively. The current-voltage measurements showed relatively lower current for ZnO nanostructured thin films, synthesized using ZnCl2 precursor, signifying the presence of zinc vacancies trap sites and is also consistent with Mott-Schottky measurements, showing lower carrier concentrations with respect to that of ZnO precursor derived ZnO nanostructured thin films. Thus, controlled Zn vacancies in ZnO nanostructured thin films may lead to the efficient green light emitters, useful for green light colour emission applications.

Analysis of the optical properties of ZnO thin films deposited on a glass substrate by the So-gel method

Zinc oxide (ZnO) has attracted the attention of researchers as a photocatalyst material, because ZnO has a wide direct band gap (3.37 eV) and is a semiconductor material with a large excitation binding energy (60 meV). ZnO is a photocatalyst that has many advantages, namely cheap, non-toxic, and theoretically very active under UV irradiation. The most interesting thing about ZnO semiconductor compared to other semiconductors is that ZnO can absorb most of the solar spectrum. However, there is a weakness of the ZnO semiconductor, namely the very fast recombination of charge carriers and the ZnO semiconductor has a low efficiency in the visible region which causes the ZnO semiconductor to have a wide band gap. that is the weakness of ZnO. it is necessary to choose the right method to overcome this deficiency of ZnO. one way that can be done is to increase the photocatalytic ability of zinc oxide, it is necessary to develop it in the manufacture of thin films. The method used in the manufacture of Thin Film is using the sol-gel spray coating method. the first stage is through the manufacture of ZnO precursors by dissolving zinc acetate dehydrate with isopropanol solvent through stirring. then the second stage by adding Monoethanolamine. This stirring lasted for 30 minutes at a temperature of 70°C, the precursor concentration was prepared with three different concentrations which included concentrations of 0.1, 0.3, and 0.5 M. ZnO precursor deposited on the substrate glass is blown at 400 °C. Optical properties are carried out by recording the transmittance and absorbance which are affected by increasing concentrations. The optical transmission spectra show that the transmission increases with decreasing concentration and the maximum transmission in the visible region is about 90% for ZnO thin films prepared with 0.1 M. The optical band gap value produced by the thin film of 0.1 M precursor concentration resulted in an energy band gap of 3.11 eV; thin films of 0.3 M precursor concentration produced an energy band gap of 3.07 eV; and thin film of 0.5M precursor concentration produced an energy band gap of 3.06 eV.©2022 JNSMR UIN Walisongo. All rights reserved.

Facile synthesis of ZnO–Ag nanocomposite supported by graphene oxide with stabilised band-gap and wider visible-light region for photocatalyst application

The synthesis of zinc oxide (ZnO), with the support of silver (Ag) and Graphene Oxide (GO), was carried out in several stages as a potential photocatalytic material. First, the GO was synthesized from commercial graphite using the Hummers’ method, and ZnO and Ag precursors were prepared. The second stage was the electrospinning process, followed by calcination. The solution in the electrospinning process, to produce the nanofibers, was a mixture of polymer (polyvinyl alcohol), zinc acetate, AgNO3, and GO. The fibres produced were thermally treated at 500 C for 2 h. XRD and FTIR analyses confirmed that GO was successfully synthesized from commercial graphite. ZnO and Ag had wurtzite and cubic hexagonal structures based on XRD and TEM characterization. The nanocomposites developed had increased photocatalyst characteristics: low band gap energy, such as 2.98 (ZnO), 2.76 (ZnO–Ag), 2.93 (ZnO-GO), and 2.75 (ZnO–Ag-GO). Furthermore, the nanocomposites had absorption characteristics in the visible light region. Using UV–Visible spectrophotometer, Diffuse Reflectance Spectroscopy, and Photoluminescence, it was explained that the Surface Plasmon Resonance effect possessed by Ag and GO nanoparticles had semiconductor properties that acted as electron trapping, thereby reducing or preventing the occurrence of electron–hole recombination. In conclusion, the ZnO nanocomposites with the addition of Ag and GO could improve the photocatalytic characteristics of ZnO with the potential for direct application in photodegradation of organic and textile waste in water.

Effect of thickness and reaction media on properties of ZnO thin films by SILAR

Zinc oxide (ZnO) is one of the most promising metal oxide semiconductor materials, particularly for optical and gas sensing applications. The influence of thickness and solvent on various features of ZnO thin films deposited at ambient temperature and barometric pressure by the sequential ionic layer adsorption and reaction method (SILAR) was carefully studied in this work. Ethanol and distilled water (DW) were alternatively used as a solvent for preparation of ZnO precursor solution. Superficial morphology, crystallite structure, optical and electrical characteristics of the thin films of various thickness are examined applying X-ray diffraction (XRD) system, scanning electron microscopy, the atomic force microscopy, X-ray photoelectron spectroscopy, ultraviolet–visible spectroscopy, photoluminescence spectroscopy, Hall effect measurement analysis and UV response study. XRD analysis confirmed that thin films fabricated using ethanol or DW precursor solvents are hexagonal wurtzite ZnO with a preferred growth orientation (002). Furthermore, it was found that thin films made using ethanol are as highly crystalline as thin films made using DW. ZnO thin films prepared using aqueous solutions possess high optical band gaps. However, films prepared with ethanol solvent have low resistivity (10–2 Ω cm) and high electron mobility (750 cm2/Vs). The ethanol solvent-based SILAR method opens opportunities to synthase high quality ZnO thin films for various potential applications.

Fluidic Manipulating of Printable Zinc Oxide for Flexible Organic Solar Cells.

As a representative electron transporting layer in organic solar cells, zinc oxide (ZnO) can be fabricated by the meniscus-guided coating with the promotion of sol-gel technology. In order to fabricate stable and flexible organic solar cells (OSCs) based on the printable ZnO layers, here, a new method for simultaneously manipulating fluidics of the sol-gel ZnO precursor and optimizing processability of the ZnO layer for flexible OSCs is developed. It is found that the Marangoni recirculation in meniscus and the annealing temperature of the sol-gel ZnO precursor can be effectively modulated by changing the Lewis base. With the use of propylamine, the high-quality ZnO layer that is suitable for flexible OSCs can be fabricated through blade coating. Under such a condition, the formation of polar facet in ZnO layer is well restrained, which favors the photostability of the cells. As a result, the best 1.00 cm2 flexible cell outputs a power conversion efficiency of 16.71%, which is the best value till now.

Photo-patterned oxide films produced using polymeric metal acrylate for low-voltage thin-film transistors

Solution-processed zinc oxide (ZnO) thin-film transistors (TFTs) have received considerable attention as key elements for future electronics due to the ease of fabricating these TFTs and due to the natural abundance and hence low cost of ZnO. However, issues regarding the patterning of solution-processed ZnO semiconductor films unfortunately continue to pose a barrier to their commercialization. In this study, we optimized nanometer-thick photo-curable zinc acrylate (ZnA) films as ZnO precursors and used these precursors to prepare photo-patterned ZnO semiconductors for the fabrication of n-type TFTs. Solution-processed ZnA films were effectively micro-patterned under UV light, because UV-irradiated ZnA film was not solved in etching solvent as a result of photocrosslinking of diacrylate moiety. Through a sol-gel reaction, wurtzite ZnO crystals were stably formed from the photo-patterned ZnA films. After optimizing the film thickness and by using a photo-patterned ZrOx dielectric layer, the prepared ZnO TFT exhibited stable performances with a low-voltage operation within ±2 V. This approach for developing a ZnO semiconductor film can be used to enable the realization of simple, inexpensive, and environmentally friendly solution-processing techniques in electronic device fields.

Enhancement of the performance of ZnO based natural dye sensitized solar cells via PVA morphology controlled nanorods

ZnO nanoparticles were synthesized via low temperature hydrothermal synthesis procedures at 90 °C using zinc nitrate hexahydrate as the zinc oxide precursors and hexamethyleneamine as the precipitating agent. The structural, surface morphology and optical studies of the hydrothermally synthesized ZnO nanoparticles revealed that the synthesized products were nano-rods, grown in very high-density with well-crystalline wurtzite hexagonal phase and good optical properties. Ployvinyl alcohol (PVA) was used as surfactant to modify the surface features of the ZnO nanorods. The ZnO nano-rods were employed as photo-anode for dye sensitized solar cell (DSSC) and were sensitized by natural dye extracted from Baphia nitida plant. The photovoltaic characteristics of the cell such as the short circuit current, open circuit voltage as well as the shunt and series resistances of the cell were studied. The incident photon to current conversion efficiency was also studied. The study revealed that the PVA improved the overall photo-conversion efficiency of the DSSC.

Low resistivity annealed tin-doped zinc oxide thin films prepared by the sol gel technique

Tin-doped zinc oxide films were obtained by mixing zinc oxide and tin oxide precursor solutions by the sol–gel technique. The tin atomic concentrations in the solution studied were 0, 2, 4, 6, 8 and 10 at %. The films were deposited by the dipping method on glass substrates. The films were sintered at 400 °C for 1 h, in an open atmosphere. A second thermal treatment in vacuum (~10-3 torr) at 500 °C for 5 min was applied in order to decrease the resistivity of the films. The X-ray diffraction patterns show the hexagonal phase of ZnO. The crystalline grain size decreases as the tin content increases. SEM measurements show a change in morphology surface when tin is added. All films show high optical transmission (~85%) and a direct band gap value of 3.2 eV. The minimum resistivity value obtained was 10-1 Ω-cm for the films with 4 at. % of tin.

Visible light sensitized porous clay heterostructure photocatalyst of zinc-silica modified montmorillonite by using tris(2,2′-bipyridyl) dichlororuthenium

A visible-light sensitization on porous clay heterostructure of zinc-silica modified montmorillonite (PCH-ZnSi) photocatalyst with tris(2,2′-bipyridyl) dichlororuthenium has been conducted. The preparation of PCH-ZnSi was performed by intercalation of surfactant and co-surfactant of cetyl trimethyl ammonium bromide-trimethanol amine followed by approaching zinc oxide and silica precursor under microwave assisted method followed by calcination, meanwhile the ruthenium complex attachment was conducted by Ru(Bpy)32+ impregnation into PCH-ZnSi. The results showed that porous clay heterostructure was successfully obtained as shown by the increased d001 of clay structure identified from XRD measurement and TEM analysis which represented the layers space ranging at 1.9-2.9 nm from 1.09 nm of montmorillonite. This increasing is in line with the evolution of pore distribution and the specific surface area enhancement. Moreover the sensitized form (Ru(Bpy)32+/PCH-ZnSi) represented the increasing photocatalytic activity in both UV and visible light exposure which corresponding to the photoluminescence spectrum ranging at visible region. The physicochemical characteristics supported the photocatalytic activity as revealed by the high degradation efficiency of methylene blue photodegradation which reached 99.8% under UV and 87.6% under visible light. The material has stability as it has maintained efficiency until 6 cycles, correlated with the availability of photoactive sites identified by XPS analysis.

Novel structure of bacteria doped ZnO particles: Facile and green synthesis route to prepare hybrid material for supercapacitor electrodes

Zinc oxide (ZnO) nanostructures/bacteria (Escherichia coli, E. coli) composite material is successfully prepared via carbonization process. Morphological and electrochemical properties of nanostructure were studied as function of concentration of bacteria solution. Morphological properties of the composite material were investigated by scanning electron microscopy (SEM) and Brunauer–Emmett–Teller (BET). The new approach of high-performance electrodes based on carbonization prepared from precursor and reductant of ZnO and bacteria resources. The ZnO nanostructures were reacted with the bacteria to introduce carbon (C) and nitrogen (N) for better electrochemical performance and an increased surface area. The bacteria doped ZnO electrode exhibited significantly enhanced specific capacitance (41F g−1) at a discharge current density of 0.5A g−1, and cycling stability of 55% retention after 5000 cycles. Therefore, the bacteria as electrical dopant gave higher specific capacitance and cycle stability to the other metal oxide which could be a potential candidate in commercial applications of supercapacitors.