Pure Oxide Research Articles

Indium-doped tungsten oxide architectures anchored on 2D rGO Matrix with enhanced visible-light-response and efficient charge separation for photocatalytic degradation of organic pollutants

Visible-light-responsive photocatalysis has been recognized as a sustainable strategy to address environmental pollution, but semiconductor-based photocatalysts often suffer from many shortcomings, including low visible light absorption and rapid recombination of photo-generated charge carriers. In this regard, rationally designed composite materials have gained substantial prominence, as achieving an ideal photocatalyst's characteristics in a single component material is frequently difficult. In the present study, we have synthesized pure (WO3) and indium-doped tungsten oxide (In-WO3) by the facile solvothermal route. The doped material was anchored on a 2D rGO matrix to fabricate the In-WO3/rGO composite. The structural, morphological, electrical, and optical properties of the as-synthesized materials were investigated as a function of doping and composite fabrication by various physical and electrochemical techniques. The comparative photocatalytic performance was evaluated by degrading Congo Red (CR) dye and paracetamol (PCM) drug. The composite material shows degradation efficiencies of ∼96 % (K=0.0174 min−1) and ∼91 % (K=0.0144 min−1) for CR dye and PCM drug, respectively. The boosted catalytic performance corresponds to the declined band gap (2.53 eV) and increased conductivity (0.1270 Sm−1), which enhances its visible light absorption and a surge in the charge carrier's population. The kinetics, relative contribution of different active species generated, and the potential mechanism of photodegradation reaction are discussed in detail. The significant increase in photocatalytic performance of the fabricated In-WO3/rGO composite discloses its promising catalytic potential for the degradation of recalcitrant organic pollutants.

Enhancing fresh strawberry preservation: Fabrication and characterization of electrospun fibers decorated with functionalized graphene oxide

AbstractThis study focuses on developing an innovative packaging material for fresh strawberries composed of electrospun poly(ε‐caprolactone) (PCL)/poly(vinylpyrrolidone) (PVP) fibers decorated by pure graphene oxide (GO) and functionalized GOs with silane agents using the electrospinning technique. Initially, synthesized GO was first functionalized by silane agents, and followed by the fabrication of electrospun PCL/PVP fibers incorporating both pure GO and functionalized GOs. The surface morphological analyses revealed the uniformity, smoothness, and beadless in the fabricated fibers. The average fiber diameter of the PCL/PVP/0.5A‐GO fibers was found as 3244 ± 56 nm. Electrospun PCL/PVP/0.5A‐GO and PCL/PVP/0.5G‐GO fibers exhibited increased water absorption ratios over 20 days. The incorporation of GO into the polymer matrix, along with an increase in GO concentration, enhanced the tensile strength of the fibers, found as 5.149 ± 0.032 kPa. In preservation tests on fresh strawberries, PCL/PVP/0.5A‐GO fibers demonstrated superior freshness compared with unpacked strawberries and other variants. The study also highlighted the inhibitory effects of fibers decorated with 0.5% APTES‐GO, showing the highest inhibition zone. In summary, fibers incorporating 0.5% A‐GO effectively extended the shelf‐life of fresh strawberries, making them a promising packaging material for perishable goods.

Research on Ozone-Enhanced Oxidation of Industrial Zinc Sulfite from Flue Gas Desulfurization

ABSTRACT This study investigates the air oxidation and ozone-enhanced oxidation of zinc sulfite. Zinc sulfite was prepared by reacting pure or industrial zinc oxide with SO2 in water. The oxidation experiments were conducted under constant temperature conditions, with slurry, oxygen, and ozone concentrations in the ranges of 0.5–4%, 10–60%, and 1100–1920 ppm, respectively. The experiments involved determining the zinc ion concentration, sulfite concentration, dissolved oxygen, ozone concentration in the exhaust gas, and total organic carbon value for analysis of the oxidation process. The findings revealed that the mass transfer rate of O2 and/or O3 determined the reaction rate in the main stage of the oxidation process, while ozone affected the non-mass transfer control stage, resulting in an average enhancement of 15% in the oxidation rate. Furthermore, ozone causes organic matter attached to industrial zinc sulfite particles to fall off into the solution, significantly improving the oxidation ratio of industrial zinc sulfite.

Influence of multi-doping (Zn and Sn) on the optical, and electrical properties of spray-deposited CdO thin films

This investigation has been focused on the spray-deposited pure cadmium oxide (CdO) thin films and also doped with zinc (Zn) and tin (Sn), as a transparent conducting oxide for optoelectronic applications. By varying the concentration of Sn (0–2%) into CdO, the microstructural, morphological, and optoelectronic properties were investigated. XRD spectra confirmed the polycrystalline cubic structure of the pure, doped, and co-doped CdO films. SEM investigation reveals the crack-free homogeneous cauliflowers-like morphology of the fabricated thin films. The existence of elemental compositions such as Cd, Zn, Sn, and O in the prepared films was confirmed by EDS analysis. All of the doped and co-doped CdO films showed good transparency in the visible range. Moreover, a slight increment has been found in the optical band gap from 2.43 eV to 2.50 eV with increasing Sn concentration, which can be explained by the Burstein-Moss phenomena. A decrement of Urbach energy was noted for an increased concentration of Sn. Besides, Zn and Sn (1 %) co-doped films exhibited the lowest electrical resistivity value 4.09×10−4 Ω-cm among other doped compositions. However, the addition of Zn and Sn into CdO thin films enhanced the optoelectronic properties.

Effect of desert-sand replacing pure SiO2 on crystallization, densification and properties of cordierite glass-ceramic

Idle desert sand was utilized to replacing pure SiO2 in raw materials to synthesize cordierite glass-ceramics. The effects of desert sand addition on sinterability, phase transformation, microstructure, and mechanical and thermal properties of the glass-ceramics were studied. Results show that glass transition temperature and the crystallization temperatures of glass to μ-cordierite and further to α-cordierite were all monotonously decreased with an increase of the replacement from 10 wt% to 90 wt%. Densification of the glass powder compacts started from 900 °C and was improved with increasing the replacement of desert sand and sintering temperature. The highest bending strength of 133.6 MPa and hardness of 936.7 HV were occurred at 90 wt% replacement when sintered at 1000 °C and 1100 °C for 2 h respectively; the lowest thermal expansion coefficient of 1.92 × 10−6/°C was achieved by a 50 wt% replacement and sintering at 1100 °C for 2 h. Desert sand addition not only introduces main compositions of SiO2, Al2O3, and MgO but also introduces nucleation agents of Fe2O3 and TiO2 and fluxes of Na2O, K2O, and CaO. These impurities had significant effect on improvement of the crystallization, densification, and properties of products. This eliminates the need for nucleation agents and fluxes that are necessary in the case of using pure oxides and minerals as raw materials.

Comparative performance of fluorite-structured materials for nanosupercapacitor applications

Over the last fifteen years, ferroelectric (FE) and antiferroelectric (AFE) ultra-thin films based on fluorite-structured materials have drawn significant attention for a wide variety of applications requiring high integration density. AFE ZrO2, in particular, holds significant promise for nanosupercapacitors, owing to its potential for high energy storage density (ESD) and high efficiency (η). This work assesses the potential of high-performance Hf1−xZrxO2 thin films encapsulated by TiN electrodes that show linear dielectric (LD), FE, and AFE behavior. A wake-up effect is observed for AFE ZrO2, a phenomenon barely reported for pure zirconium oxide and AFE materials in general, correlated with the disappearance of the pinched hysteresis loop commonly observed for Zr-doped HfO2 thin films. ESD and η are compared for FE, AFE, and LD samples at the same electrical field (3.5 MV/cm). As expected, ESD is higher for the FE sample (95 J/cm3), but η is ridiculously small (≈55%) because of the opening of the FE hysteresis curve, inducing high loss. Conversely, LD samples exhibit the highest efficiency (nearly 100%), at the expense of a lower ESD. AFE ZrO2 thin film strikes a balance between FE and LD behavior, showing reduced losses compared to the FE sample but an ESD as high as 52 J/cm3 at 3.5 MV/cm. This value can be further increased up to 84 J/cm3 at a higher electrical field (4.0 MV/cm), with an η of 75%, among the highest values reported for fluorite-structured materials, offering promising perspectives for future optimization.

Greenly engineered bimetallic Ag-ZnO nanohybrids for synergistic antibacterial enhancement

The escalating issue of infectious agents developing resistance to traditional antibiotics has spurred ongoing research into effective and broad-spectrum antimicrobial solutions. This study focuses on the fabrication of silver-zinc oxide Nanohybrids (A-ZnO-NHs) with varying silver content (1 %, 3 %, 5 %) using a simplified modified sol–gel method, further enhanced by a green synthesis approach utilizing orange peel extract for the generation of silver nanoparticles. The physicochemical characteristics of the A-ZnO-NCs were thoroughly examined. X-ray diffraction analysis verified the presence of Ag nanoparticles within the zinc oxide and scanning electron microscopy revealed the nanoscale silver particles uniformly distributed on the spherical zinc oxide nanoparticles. Transmission electron microscopy indicated that the Ag-ZnO-NCHs ranged in size from 10 to 20 nm. X-ray photoelectron spectroscopy analysis confirmed the formation of strong chemical bonds between the silver and zinc oxide surfaces in the nanohybrids. This study explored into the structural, morphological, and antimicrobial characteristics of the A-ZnO-NHs at different compositions. The bactericidal efficiency of the A-ZnO-NHs was assessed against both gram-positive and gram-negative bacterial strains. The impact of the A-ZnO-NHs on the cellular structure and chemical composition of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) was also explored. The findings revealed that the A-ZnO-NHs with 3 % silver content demonstrated higher antimicrobial activity against E. coli and S. aureus compared to other compositions and pure zinc oxide nanoparticles. The antimicrobial activity decreases when the concentration of silver increases because the silver particles agglomerate together, reducing their surface area and lessening their effectiveness as antibacterial agents, despite their potential for various applications.

Incorporation of zinc oxide and cobalt doped zinc oxide nano-rods in commercial sunscreen sample to optimize its UV-ray absorption

In the last two decades, the ozone layer in the atmosphere has been depleted, and the sun rays are now more harmful to human skin because they no longer filters it completely. Long-term exposure to harmful ultraviolet rays (UV-rays), which have wavelengths between 220 nm and 380 nm, causes catastrophic damage to skin cells. Sunscreens are therefore absolutely necessary to protect the skin. The co-precipitation method was used to synthesize both pure and cobalt-doped zinc oxide nano structures. In sunscreens, these nanostructures serve as a UV filter. The obtained nano structures have been characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), and diffuse reflectance spectroscopy (DRS). The ability of a sunscreen sample containing nano structures to yield results for a period of various hours at different temperatures (20 °C, 30 °C, and 50 °C) has been tested. According to XRD results, prepared samples exhibits hexagonal wurtzite crystalline structures and are of 22 nm in size for pure zinc oxide and 20 nm in size for cobalt- doped zinc oxide. SEM was used to find morphologies, i.e., nano rods (NRs) at 200 nm and 2 μm. DRS provided evidence of sunscreen’s endurance, with a 97% absorption of UV-rays at 50 °C for up to 6 h when incorporated with NRs. In order to boost UV-ray absorption in sunscreen, nanotechnology has been successfully applied.

A Comprehensive Investigation of Methanol Electrooxidation on Copper Anodes: Spectroelectrochemical Insights and Energy Conversion in Microfluidic Fuel Cells.

Here, we comprehensively investigated methanol electrooxidation on Cu-based catalysts, allowing us to build the first microfluidic fuel cell (μFC) equipped with a Cu anode and a metal-free cathode that converts energy from methanol. We applied a simple, fast, small-scale, and surfactant-free strategy for synthesizing Cu-based nanoparticles at room temperature in steady state (ST), under mechanical stirring (MS), or under ultrasonication (US). The morphology evaluation of the Cu-based samples reveals that they have the same nanoparticle (NP) needle-like form. The elemental mapping composition spectra revealed that pure Cu or Cu oxides were obtained for all synthesized materials. In addition to having more Cu2O on the surface, sample US had more Cu(OH)2 than the others, according to X-ray diffractograms and X-ray photoelectron spectroscopy. The sample US is less carbon-contaminated because of the local heating of the sonic bath, which also enhances the cleanliness of the Cu surface. The activity of the Cu NPs was investigated for methanol electrooxidation in an alkaline medium through electrochemical and spectroelectrochemical measurements. The potentiodynamic and potentiostatic experiments showed higher current densities for the NPs synthesized in the US. In situ FTIR experiments revealed that the three synthesized NP materials eletcrooxidize methanol completely to carbonate through formate. Most importantly, all pathways were led without detectable CO, a poisoning molecule not found at high overpotentials. The reaction path using the US electrode experienced an additional round of formate formation and conversion into carbonate (or CO2 in the thin layer) after 1.0 V (vs. Ag/Ag/Cl), suggesting improved catalysis. The high activity of NPs synthesized in the US is attributed to effective dissociative adsorption of the fuel due to the site's availability and the presence of hydroxyl groups that may fasten the oxidation of adsorbates from the surface. After understanding the surface reaction, we built a mixed-media μFC fed by methanol in alkaline medium and sodium persulfate in acidic medium. The μFC was equipped with Cu NPs synthesized in ultrasonic-bath-modified carbon paper as the anode and metal-free carbon paper as the cathode. Since the onset potential for methanol electrooxidation was 0.45 V and the reduction reaction revealed 0.90 V, the theoretical OCV is 0.45 V, which provides a spontaneous coupled redox reaction to produce power. The μFC displayed 0.56 mA cm-2 of maximum current density and 26 μW cm-2 of peak power density at 100 μL min-1. This membraneless system optimizes each half-cell individually, making it possible to build fuel cells with noble metal-free anodes and metal-free cathodes.

Unveiling the diffusion pathways under high-temperature oxidation of Cr2AlC MAX phase via nanoscale analysis

The MAX phase chromium aluminium carbide (Cr2AlC) is a potential candidate for high-temperature structural and energy applications due to the unique combination of properties, including excellent oxidation and corrosion resistance in harsh environmental conditions. In this work, the oxidation behaviour of bulk Cr2AlC was studied at temperatures of 1000 °C and 1200 °C in humid synthetic air, mimicking a realistic application environment. An α-Al2O3 scale forms at both temperatures, consisting of both inward and outward-growing layers, with a continuous Cr7C3 layer beneath the oxide. A special focus was put on employing atom probe tomography (APT) to analyse the oxide and carbide layers at the nanoscale. Decomposition of Cr2AlC to Cr7C3 is the main source (>70%) of aluminium needed for the oxide scale formation, while Al depletion in the underlying MAX phase remains marginal (<1 at%), exhibiting a pattern different from the common high-temperature oxidation of alloys. Al diffusion to the oxide scale proceeds predominantly through grain boundaries (GBs) in Cr2AlC and through the bulk in Cr7C3. Ionic diffusion through GBs of the large-grained inner alumina layer seems to be the rate-limiting step for the oxide scale growth, resulting in the apparent parabolic oxidation kinetics. No segregation of Cr, C or any impurities, which could affect ionic transport, was found at these alumina GBs by APT, rendering the results of this study as characteristic of a pure Cr2AlC oxidation.

Characterization of graphene–TiO2-deposited semi-organic solar cell

High energy supply is critical, particularly in developing countries, to maintain lifestyles as the world's population and technological-economic metropolis grow. Solar photovoltaic cells have been used as an alternative to generate renewable, sustainable, and green energy for the past two decades. In general, the materials employed in the photoanode part are critical to manufacturing high-efficiency solar cells with 14–18% efficiency. A simple and successful method has been discovered for creating a film composed of graphene sheets and 99.8% pure anatase titanium oxide (TiO2) nanoparticles. After sensitization, the films were tested as photoelectrodes for dye-sensitized solar cells. The experimental results show that using an optimized graphene material considerably improves the power conversion efficiency of the cells, resulting in a 45% increase in short-circuit current density ( JSC). This study uses capsician as a bonding agent to enhance the current density of a graphene–TiO2 based semi-organic solar cell. The mechanical and electrical properties of the cell are investigated using a scanning electron microscope, energy dispersive X-ray, and Corescan.

Redox Stability and Electrical Properties of a Series of Novel Quadruple Dopant BIMEVOX: Bi2V1−4x(CuNiNbTi)xO5.5−δ

Bi2VO5.5‐based materials are well‐known oxide ion conductors owing to their exceptionally high ionic conductivity. However, their poor phase and redox stabilities under a reducing atmosphere hinder their practical application as electrolytes for solid oxide fuel cells. Here, a series of novel quadruple metal‐doped bismuth vanadium system materials Bi2V1−4x(CuNiNbTi)xO5.5−δ (0 ≤ x ≤ 0.1) are prepared through a traditional solid state reaction method, aiming to enhance the phase and redox stability under reducing atmosphere. The results reveal that multiple‐metal‐doping can stabilize the tetragonal phase of Bi2VO5.5 to room temperature and show good phase and structural stabilities under inert or high oxygen partial pressure atmospheres, as well as pure oxide ion conduction which is slightly lower than that of the parent material. However, under a reducing environment, the Bi2V1−4x(CuNiNbTi)xO5.5−δ materials would still undergo a phase decomposition, yielding elemental bismuth impurity, and introducing strong electronic conduction. Thus, how to improve the phase and redox stabilities under the reducing atmosphere of the Bi2VO5.5‐based materials is still the endeavor direction in the future.

BATCH COMPOSITION INFLUENCE ON SINTERING AND CRYSTALLIZATION PROCESSES OF CORDIERITE GLASSES OBTAINED BY THERMAL PLASMA MELTING

This article focuses on the production of glasses and glass-ceramic materials with a cordierite (2MgO∙2Al2O3∙5SiO2) composition. The processes of crystallization and sintering of cordierite glasses, which are based on natural raw materials, pure oxides and pre-synthesized cordierite, have been investigated. It has been determined that cordierite glasses produced via plasma melting exhibit high structural defects attributed to rapid heating and cooling rates. The relaxation of microstresses in the glasses takes place within the temperature range of 480 – 490 °C. Glasses based on synthesized cordierite exhibit a crystallization temperature of 930 – 1020 °C, depending on the presence and type of nucleating agents. This is approximately 20 – 50 °C lower compared to glasses based on component mixtures. The primary crystallization product of studied glasses at 900 °C is the high-quartz solid solution with formula MgO∙Al2O3∙3SiO2, which is dissociate above 1000 °C with the formation of cordierite. The addition of 5% ZrO2 to the batch increases the viscosity of softened glasses and their crystallization temperature, resulting in increased activity of glass powders in the sintering processes due to the higher impact of liquid-phase sintering on the general densification process of glass-ceramics. This allows for the production of glass-ceramics with open porosity of 2 – 4% at 1300 – 1350 °C. The addition of 5% TiO2 to the batch reduces the glass crystallization temperature. However it does not significantly effect on the cordierite glass-ceramics sintering processes. For citation: Sharafeev S.M., Shekhovtsov V.V., Zvyagina E.E. Batch composition influence on sintering and crystallization processes of cordierite glasses obtained by thermal plasma melting. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 7. P. 80-87. DOI: 10.6060/ivkkt.20246707.7032.

Construction of three-dimensional polyethyleneimine incorporated graphene oxide aerogels as high-capacity electrode for enhanced uranium(VI) electrosorption performance

Electrosorption technique is paid more attention in recovery of uranium(VI) due to its low energy consumption, green process and easy regeneration, but still is hindered by the limited accessible active sites on the electrode material, poor surface wettability and inherent ion exclusion effects. Herein, novel there dimensional porous polyethyleneimine/graphene oxide aerogel (PEI/GOA) electrode was constructed by incorporating polyethyleneimine into graphene oxide and using chitosan as binder for uranium(VI) electrosorption. The synthesized PEI/GOA had a stable three-dimensional porous structure, high specific capacitance (54.06F/G) and good charge–discharge stability. The electrosorption process of uranium(VI) by PEI/GOA electrode was affected by applied voltage and pH, fitted by the pesuo-second-order kinetics and Langmuir model. The maximum theoretical electrosorption capacity of uranium(VI) by PEI/GOA electrode at − 1.2 V was 419.71 mg/g, which was 2.2 times higher than that of pure graphene oxide electrode. PEI/GOA electrode exhibited less than 20 % loss after five cycles using 0.1 M NaHCO3 as the eluent. The efficient U(VI) electrosorption by PEI/GOA electrode was not only attributed to the formation of the electric double layer, but also due to the interaction and synergy of the –NH2, –CONH- and –OH on the PEI/GOA electrode. This research offers a new approach for the efficient removal of uranium (VI) from uranium-containing wastewater.

Synthesis and photocatalytic properties of Cerium(IV) oxide graphene oxide composites

Semiconductor photocatalytic technology is a simple, efficient, and low-cost method for environmental pollution remediation. Cerium dioxide (CeO2), as a promising oxidative degradation photocatalyst, can solve the problems of energy shortage and environmental pollution. In this paper, cerium dioxide/graphene oxide composites were successfully synthesized by a one-pot hydrothermal method, achieving a degradation rate of 88.96 % for rose red dye in 150 min, and the introduction of reduced graphene oxide effectively improves the photocatalytic performance of pure cerium oxide.

Sustainable recovery of rare earth elements from Ni-MH batteries: Flux-free thermal isolation and Subsequent hydrometallurgical refinement

This study details a sustainable approach for efficient recovery of highly pure rare earth elements oxides (REOs) from Ni-MH batteries. REOs (i.e., La, Ce, Sm, Nd, and Pr oxides) were thermally isolated from spent Ni-MH batteries into an oxide phase with the REO concentration of 67.4 wt%. Subsequently, separate leaching processes were conducted using sulfuric acid and hydrochloric acid solutions, and the results were compared in terms of efficiency and feasibility. Sodium REEs sulfate hydrate (NaRE(SO4)2.xH2O) was precipitated from the sulfuric acid leachate by adjusting the pH to 1.5 using sodium hydroxide, while the addition of oxalic acid to the hydrochloric acid leachate enabled the recovery of REEs as oxalate hydrate (RE2(C2O4)3.xH2O). The resulting sulfate salt was mixed with a sodium hydroxide solution, leading to the formation of REEs hydroxide. The REEs hydroxide and oxalate were calcined at 1000 °C, resulting in the production of REOs with a purity exceeding 99.7%. This research demonstrates the feasibility of developing an efficient, environmentally friendly, and sustainable approach for the recovery of highly pure REOs from Ni-MH batteries which potentially can minimize the environmental impact associated with the extraction of REOs from virgin sources, while addressing the challenge of effective recycling of end-of-life Ni-MH batteries.

Rapidly chemical preparation of Mn doped ZnO nanostructures for photocatalysis efficiency based on UV light system and mechanism insights

Through a facile chemical precipitation process, pure zinc oxide (ZnO) and various ratio of Mn-doped zinc oxide (Zn1-xMnxO) nanostructured materials were synthesized. The degradation of an azo dye acid orange 2 (AO-2) solution under UV light was investigated using the synthesized materials as photocatalysts. XRD, FTIR, DLS, FESEM, EDS, PL, BET, magnetic, TGA and UV–vis techniques were used to elucidate the structural, functional, particle, elemental, morphological, and optical aspects of the catalysts. The XRD and FESEM analysis showed the hexagonal ZnO structure and spherical shape of the ZnO nano-photocatalyst, respectively. The crystal sizes of Zn1-xMnxO are 27.40–38.31 nm. The optical band gap energy of Zn1-xMnxO are 2.53–3.10 eV. Under UV irradiation for 60 min, MZ-25 NPs demonstrated better degradation (100.0%) of AO-2 dye. The effect of various factors such as catalyst quantity, and pH of the dye solution on the rate removal was investigated. After 60 min of UV light irradiation, dye removal was obtained under ideal conditions (with catalyst loading of 3 mgL−1, and pH 4). The rate constant values of MZ-25 sample are determined to be 0.0219 min−1. The scavenging test reveals that ∙O2 − and ∙OH are responsible for the photo-degradation of AO-2 dye.

Improvement of chemical mechanical polishing performance by introducing N–Si bond via external coating of cerium oxide with ZIF-8

Cerium oxide (CeO2) nanoparticles are widely used as abrasives in chemical mechanical polishing (CMP), an essential process for obtaining Si wafers with excellent surface quality. While CeO2 nanoparticles form Ce–O–Si bonds, which exhibit good CMP performance, their low activity results in a low removal rate. To address this issue, a two-step ultrasonic dispersion method was employed to prepare a uniform nuclear@shell CeO2@ZIF-8. The process of chemical bond generation in CMP was studied using spherical aberration-corrected transmission electron microscopy and X-ray photoelectron spectroscopy. In comparison to pure cerium oxide, the formation of Ce–O–Si bond was observed, and notably, the emergence of N–Si bond originating from the N of the ZIF-8 shell was identified. Coupled with the increased Ce3+ content, these developments enhanced CMP performance. The material removal rate (MRR) of the CeO2@ZIF-8 abrasives was 151.507 nm/min, which is 89.72 % higher than that of the pure CeO2 abrasives. Moreover, the surface roughness, as determined via AFM testing, was reduced to 0.231 nm within the confines of a 5.0 × 5.0 μm² region. Therefore, this study introduces a novel concept for CMP research by developing a CeO2@ZIF-8 compound abrasive to create a new N–Si bond.

Enhancement and refinement of SSP method for XRD analysis and investigation of structural properties of pure and Ca-doped zinc oxide

Enhancement and refinement of SSP method for XRD analysis and investigation of structural properties of pure and Ca-doped zinc oxide

An outstanding photocatalytic performance of CNTs based nanocomposite of ternary metal oxides towards cationic and anionic dyes and pharmaceutical drug

Currently, hetero-metallic oxides and their nanocomposites with 1D materials have a tremendous role in photocatalytic applications, mainly for the removal of organic effluents, due to their higher potential of electron-hole pair migration and separation than pure metal oxide NPs. The present work reports the fabrication of ternary metal oxides nanostructure (WO3·Ag2O·CuO) and its nanocomposite with carbon nanotubes (WO3·Ag2O·CuO/CNTs) using a facile approach i.e. ultra-sonication. The photocatalytic removal efficacy of fabricated nanocomposite i.e. WO3.Ag2O.CuO/CNTs along its counterpart (WO3·Ag2O·CuO) was evaluated using a model cationic dye (Methylene blue, MB), an anionic dye (Congo red, CR), and an analgesic drug (Paracetamol). The catalytic experiment was performed under natural sunlight upon light irradiation of about 90 min and using 30 mg of photocatalyst for all chosen effluents. The obtained results deduced that WO3·Ag2O·CuO/CNTs nanocomposite showed catalytic efficiency of about 97 % for MB, 87 % for CR, and 93 % for Paracetamol while it was about 80 % for MB, 74 % for CR, and 79 % for drug using WO3·Ag2O·CuO as photocatalyst. The rate constant values of nanocomposite for the removal of MB, CR, and Paracetamol are 0.037 min−1, 0.023 min−1, and 0.027 min−1 respectively. The remarkable degradation performance of WO3·Ag2O·CuO/CNTs nanocomposite as compared to ternary metal oxide (WO3·Ag2O·CuO) was due to its high charge separation, high surface area, and availability of large number of active sites for the adsorption of pollutant molecules. Hence, WO3·Ag2O·CuO/CNTs nanocomposite could be a competent photocatalyst for the removal of variety of industrial effluents i.e. organic dyes and pharmaceutical drugs etc.