Molar Ratio Of ZnO Research Articles

Enhancement of Visible Light Antibacterial Activities of Cellulose Fibers from Lotus Petiole Decorated ZnO Nanoparticles.

Cellulose/ZnO (CZ) nanocomposites are promising antimicrobial materials known for their antibiotic-free nature, biocompatibility, and environmental friendliness. In this study, cellulose fibers extracted from lotus petioles were utilized as a substrate and decorated with various shapes of ZnO nanoparticles (NPs), including small bean, hexagonal ingot-like, long cylindrical, and hexagonal cylinder-shaped NPs. Increasing zinc salt molar concentration resulted in highly crystalline ZnO NPs forming and enhanced interactions between ZnO NPs and -OH groups of cellulose. The thermal stability and UV-visible absorption properties of the CZ samples were influenced by ZnO concentration. Notably, at a ZnO molar ratio of 0.1, the CZ 0.1 sample demonstrated the lowest weight loss, while the optical band gap gradually decreased from 3.0 to 2.45eV from the CZ 0.01 to CZ 1.0 samples. The CZ nanocomposites exhibited remarkable antibacterial activity against both Staphylococcus aureus (S. aureus, Gram-positive) and Escherichia coli (E. coli, Gram-negative) bacteria under visible light conditions, with a minimum inhibitory concentration (MIC) of 0.005mg/mL for both bacterial strains. The bactericidal effects increased with higher concentrations of ZnO NPs, even achieving 100% inhibition. Incorporating ZnO NPs onto cellulose fibers derived from lotus plants presents a promising avenue for developing environmentally friendly materials with broad applications in antibacterial and environmental fields.

Synthesis of ZnO nanosheets @In2O3 hollow micro-rods heterostructures for enhanced ethanol gas sensing performance

In this paper, the ZnO nanosheets @In2O3 hollow microrods heterostructures were successfully prepared by co-precipitation and annealing methods. It was observed by SEM and TEM that the surface of the In2O3 hollow microrods was uniformly coated with porous ZnO nanosheets, which increased the specific surface area of ZnO@In2O3 composites. The In2O3 hollow microrods functions as electron transport channels and facilitate the transfer of electrons between ZnO nanosheets, consequently elevating the base resistance of sensors. The maximum sensor response of ZnO@In2O3-2 (the molar ratio of ZnO and In2O3 is 5:2) was 269.1 for 100 ppm ethanol at the optimal working temperature of 200 ºC, which is about 30.9 times higher than that of pure ZnO nanosheets (8.7) and 19.1 times higher than that of pure In2O3 (14.1). Additionally, the ZnO@In2O3-2 composites exhibit rapid response-recovery times, excellent selectivity and favorable stability. The improved gas sensing performance of ZnO@In2O3-2 heterostructures were ascribed to its heterogeneous structure building, abundant oxygen vacancies, large specific surface area and internal electric field through characterized by XPS, EPR, and BET.

Photocatalytic activity of zinc oxide nanorods incorporated graphitic carbon nitride catalyst

Background: Photocatalysts are user-friendly and serve as compatible materials for degrading industrial dye pollutants. This study utilizes zinc oxide/graphitic carbon nitride (ZnO/g-C3N4) nanocomposites against degrading methylene blue (MB). Methods: The hydrothermal method assisted sonication technique was used to fabricate the ZnO/g-C3N4 composite with varying ratios of ZnO/g-C3N4 (1:0.25, 1:0.50, 1:1). The synthesized materials have undergone various sophisticated techniques for finding their physiochemical properties and have been utilized for photodegradation activities. Significant Findings: The characterized results exhibit that the nanoflakes of g-C3N4 were covered with nanorods of zinc oxide when observed through scanning electron microscopy (SEM). Furthermore, the X-ray diffraction (XRD) studies demonstrate that the ZnO/g-C3N4 material was successfully synthesized. The X-ray photoelectron spectra (XPS) and Fourier-transform infrared (FTIR) spectra revealed the present oxidation states and chemical bonding of the materials. The photocatalytic activity results demonstrated that the concentration of ZnO molar ratio in varying g-C3N4 significantly affected the decomposition performance. The ZnO/g-C3N4 (1:0.50) presented a higher rate of degradation, reaching 92% at 120 minutes under UV light and 65% at 240 minutes under visible light irradiation. This could be explained by the mechanism that follows the separation of charge carriers, thereby producing hydroxyl radicals for the effective degradation of MB pollutants.

Preparation of S-Scheme g-C3N4/ZnO Heterojunction Composite for Highly Efficient Photocatalytic Destruction of Refractory Organic Pollutant

In this study, graphitic carbon nitride (g-C3N4)-based ZnO heterostructure was synthesized using a facile calcination method with urea and zinc nitrate hexahydrate as the initiators. According to the scanning electron microscopic (SEM) images, spherical ZnO particles can be seen along the g-C3N4 nanosheets. Additionally, the X-ray diffraction (XRD) analysis reveals the successful synthesis of the g-C3N4/ZnO. The photocatalytic activity of the synthesized catalyst was tested for the decolorization of crystal violet (CV) as an organic refractory contaminant. The impacts of ZnO molar ratio, catalyst amount, CV concentration, and H2O2 concentration on CV degradation efficiency were investigated. The obtained outcomes conveyed that the ZnO molar ratio in the g-C3N4 played a prominent role in the degradation efficiency, in which the degradation efficiency reached 95.9% in the presence of 0.05 mmol of ZnO and 0.10 g/L of the catalyst in 10 mg/L of CV through 120 min under UV irradiation. Bare g-C3N4 was also tested for dye decolorization, and a 76.4% dye removal efficiency was obtained. The g-C3N4/ZnO was also tested for adsorption, and a 32.3% adsorption efficiency was obtained. Photocatalysis, in comparison to adsorption, had a dominant role in the decolorization of CV. Lastly, the results depicted no significant decrement in the CV degradation efficiency in the presence of the g-C3N4/ZnO photocatalyst after five consecutive runs.

Lotus-bud like hexagonal ZnO/g-C3N4 composites for the photodegradation of benzene present in aqueous solution

This study used a one-pot paralysis approach to combine hexagonal ZnO lotus buds with graphitic carbon nitride (g-C3N4) nanosheets to create ZnO/g-C3N4 composites. For the purpose of investigating the charge carrier interface for photocatalytic improvement, ZnO/g-C3N4 composites in various molar ratios of ZnO and g-C3N4 were produced. X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectroscopy, ultraviolet–visible diffuse reflectance spectroscopy (UV-DRS), and electrochemical impedance spectroscopy (EIS) were used to investigate the coupling of the ZnO particles to the g-C3N4 nanosheets. For the degradation of benzene, pure ZnO, pure g-C3N4, and their composites were utilized. High purity ZnO with a clearly defined hexagonal wurtzite crystal phase was shown by elemental mapping and XRD patterns, and optical characteristics measured by UV-DRS, PL spectroscopy, and spectroscopy of electrochemical impedance (EIS). For the degradation of benzene, pure ZnO, pure g-C3N4, and their composites were employed. High purity and a clearly defined hexagonal wurtzite crystal phase were revealed by elemental mapping and XRD patterns for ZnO, and optical properties examined by UV-DRS, PL spectroscopy, and EIS revealed improved visible light absorbance with a substantially reduced electron-hole recombination rate. The prepared samples were applied to test the photodegradation of benzene in the presence of visible light. The 40 %ZnO/g-C3N4 sample shown the largest photocatalytic activity for the degradation among all the produced samples, with high stability up to five cycles. The combined photocatalyst and degradation mechanism were proposed as a Z-scheme.

Oxygen vacancy and facet engineering of cuprous oxide by doping transition metal oxides for boosting alcohols selectivity in electrochemical CO2 reduction

Nanostructured Cu-based catalysts have gained much attention for electrochemical CO2 reduction (ECR) to value-added alcohols, while they are facing the challenges of unsatisfactory catalytic activity and selectivity. Herein, oxygen vacancy and facet engineering strategies are employed to modulate the ECR performance of Cu2O by doping transition metal oxides (TMOs). TMOs doping improves CO2 conversion by suppressing hydrogen evolution reaction (HER). The catalyst doped with 0.001 mol% ZnO exhibits a high alcohols Faradaic efficiency of 63.67% at −0.3 V vs. RHE, which exceeds that of the bare Cu2O (35.4%). The enhanced activity and alcohols selectivity is ascribed to the enriched oxygen vacancy defects (57.26%) for enhanced CO2 adsorption and activation and the synergistic effect between Cu and Zn sites for facilitated CO* protonation and C–C coupling. Alcohols selectivity increases from 56.87% to 64.27% and then declines to 63.67% with the increasing ZnO molar ratio from 0.00025 to 0.001. The Cu2O–ZnO-0.0005 catalyst features the octahedral structure (enclosed by the (111) and (100) facets) exhibits favorable ECR performance with the highest alcohols selectivity of 64.27% at −0.3 V vs. RHE. The enhanced alcohols selectivity is associated with the facet-dependent effect, as the exposed (111) facet favors CO2 adsorption and activation in ECR.

Fabrication of novel ZnO@BiOBr/UiO-66-NH2 core-shell heterojunction for improved tetracycline degradation

A novel ternary heterojunction of ZnO-nanorods/BiOBr/UiO-66-NH2 Z-scheme with improved charge separation ability was prepared and characterized by XRD, FTIR, XPS, FE-SEM, EDX, TEM, HRTEM, BET, UV–vis DRS, PL, EIS, and TGA analyses. The degradation of the tetracycline (TC) by the synthesized photocatalyst was investigated at the optimal molar ratio of ZnO: BiOBr: UiO-66-NH2 = 3: 1: 0.17. The ternary heterojunction showed significant development in photodegradation compared with ZnO/BiOBr, and pure UiO-66-NH2. The optimal operational conditions were determined by the Box-Behnken design at pollutant concentration = 20 ppm, catalyst dose = 0.48 g/L, pH = 7.2 and irradiation time = 90 min. The maximum degradation efficiency reached 96.6 % at the optimum conditions. In addition, at optimal conditions, the effect of immobilization of the ternary photocatalyst was investigated on FTO, and the TC degradation efficiency was about 98.2 %. The new ternary heterojunction showed good chemical stability and recoverability after 4 cycles. Based on the trapping experiments, O2–• and OH• improved the degradation process of TC. The toxicity test was studied by the growth of Escherichia coli bacteria and confirmed the rapid toxicity removal process by ZnO-nanorods/BiOBr/UiO-66-NH2 photocatalysis.

Synthesis and characterization of a g-C3N4/TiO2-ZnO nanostructure for photocatalytic degradation of methylene blue

In this study, graphitic carbon nitride (g-C3N4) nanostructures with different molar ratios of ZnO and TiO2 (i.e. g-C3N4/TiO2, g-C3N4/ZnO, and g-C3N4/TiO2-ZnO) were synthesized. The synthesized samples were characterized using field-emission scanning electron microscopy (FE-SEM), x-ray diffraction, Brunauer–Emmett–Teller (BET) analysis, and ultraviolet (UV)–visible diffuse reflectance spectroscopy (UV-vis-DRS) techniques. The FE-SEM images showed the surface morphology of each sample. The UV-vis-DRS results indicated that the bandgap of TiO2 was reduced by adding g-C3N4 and different molar ratios of ZnO. The results obtained from BET analysis confirmed that the surface area of the g-C3N4/TiO2-ZnO (1:10) nanostructure was 97.494 cm2 g−1, which was comparatively higher than other nanostructures, and became suitable for photocatalytic activity. The photocatalytic activity of the g-C3N4/TiO2-ZnO nanostructure was performed by photo-degradation of methylene blue (MB) dye under simulated solar light. The results of the photocatalytic activity showed that the synthesized nanostructure had good degradation under UV and visible light irradiation by 94.6% and 62.4%, respectively. Also, the kinetics of the photocatalytic degradation confirmed that degradation of MB dye in the presence of UV light was faster than visible light. Furthermore, a study of the reusability of the nanostructure exhibited good photo-stability and activity after six runs.

Slow Photon-Enhanced Heterojunction Accelerates Photocatalytic Hydrogen Evolution Reaction to Unprecedented Rates

Slow Photon-Enhanced Heterojunction Accelerates Photocatalytic Hydrogen Evolution Reaction to Unprecedented Rates

Spontaneous polarisation of ferroelectric BaTiO3/ZnO heterostructures with enhanced performance in a Fenton-like catalytic reaction

Ferroelectric BaTiO 3 /ZnO heterojunction catalysts synthesised via the sol–gel method present obvious enhancements in spontaneous polarisation-driven Fenton-like catalytic activity. In this study, the oxidative decomposition of methylene blue (MB) dye was used as a model reaction. Pure BaTiO 3 -activated potassium monopersulphate (PMS) could decompose up to 48% of MB dye in an aqueous solution after 40 min. MB degradation rate firstly increased and then decreased as the ZnO content of the ferroelectric BaTiO 3 /ZnO heterojunction materials was increased. The maximum degradation rate of 100% and good cycling stability were observed when the BaTiO 3 :ZnO molar ratio was 1:1. Three active species, namely, holes (h + ), sulphate radicals (SO 4 •− ) and hydroxyl radicals (OH • ), were produced following the spontaneous polarisation-driven catalytic degradation of the dye. Amongst these species, h + and SO 4 •− were the main active species. Enhancements in the Fenton-like catalytic activity of BaTiO 3 /ZnO may be attributed to the formation of semiconductor heterojunctions, which could improve the spontaneous polarisation strength of ferroelectric BaTiO 3 , promote the effective separation of e − –h + pairs and accelerate PMS activation. In summary, a novel PMS activation method was developed to provide a nontoxic, efficient and environmentally friendly technology for the degradation of organic pollutants.

Structure–property relationship and spectroscopic studies of BaO–B2O3 oxide glasses containing ZnO for optical applications

In the present work, samples of barium borate glasses containing different molar ratios of ZnO were prepared using the conventional melt-quenching technique. X-ray diffraction studies confirmed the amorphous nature of the studied materials. Structural analysis using FT-Infrared confirmed the incorporation of the Zn atom in the glass matrix as a ZnO4 unit and the existence of ZnO in the tetrahedral interstitial sites. TEM images for the studied materials show that the average particle size is about 20nm and the ZnO4 structural units reside in the glass matrix with high homogeneity. Density and molar volume studies manifested an increase in the density as the amount of ZnO increases and a subsequent decrease in the molar volume. UV absorption studies showed a blue shift in the absorption peak from 343nm to 315nm. Additionally, an observed reversible behavior around 338nm divides the absorption range into high energy and low energy regions. In the high energy region, both absorbance, absorption coefficient, and refractive index increased with ZnO content increment. In the low energy region, this behavior was reversed, and the calculated values of the refractive index agreed with the measured ones in this region. Studies of optical dielectric parameters showed a Debye-type relaxation process in which increasing the ZnO content shortens the sample relaxation time. Our results, collectively, suggest the studied materials for several optoelectronic device applications such as high-energy optical filters, optical switches, and frequency converters.

Experimental Study on Influence of Al2O3, CaO and SiO2 on Preparation of Zinc Ferrite

Gossan ore of sulfide zinc deposit contains abundant zinc, iron, and other metal elements, which is a significant resource with complex components and can be utilized. In this study, a new technology of preparing zinc ferrite from zinc sulfide deposit gossan was proposed. The effects of Al2O3, CaO, and SiO2 in gossan on the formation of zinc ferrite were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and specific surface area and pore size analysis (BET). The results show that the presence of Al2O3 and CaO could hinder the formation of zinc ferrite, while silica had no effect on the formation of zinc ferrite. Under the conditions of the molar ratio of ZnO and Fe2O3 to Al2O3, CaO, and SiO2 of 1:1:1, an activation time of 60 min, and a roasting temperature of 750 °C for 120 min, the products, which had good crystallinity, smooth particle surface, and uniform particle size could be obtained. In addition, compared to the roasted products with Al2O3 and CaO, the specific surface area, pore volume, and pore size of the products with SiO2 were the largest.

Effect of ZnO–Ag on dielectric properties of ZnO–Ag/P(VDF-TrFE-CTFE) composites

Zinc oxide-silver (ZnO–Ag) particles and ZnO–Ag/poly(vinylidene fluoride-trifluoroethylene-chlorotrifluoroethylene)[P(VDF-TrFE-CTFE)] composites were synthesized by a reflux method and a solution route, respectively. The functions of ZnO and Ag particles on the dielectric properties of the composites were investigated. The effect of the molar ratio of ZnO to Ag on the composites was also studied. The results indicated that the optimum molar ratio of ZnO to Ag in the composites with 30 wt.% fillers was 0.6/0.4 for dielectric constant modifier applications. Furthermore, the optimum composite had a dielectric constant of 56 and a dielectric loss of 0.27 at 100 Hz and room temperature. Highlights for paper: The ZnO–Ag/P(VDF-TrFE-CTFE) exhibits excellent dielectric properties. ZnO is mainly used to distribute the Ag particles. Ag is mainly used to improve the dielectric constant of composites.

Sensitivities of a 6:4 (by molar ratio) ZnO/WO3 composite nanoparticle sensor to reducing and oxidizing gases

For n–n composite nanoparticle gas sensors the dependence of the sensitivities of composite nanoparticle sensors to reducing and oxidizing gases on the molar ratio of the two n-type semiconducting materials is not established yet. In this study, the following hypothesis has been made for the ZnO/WO3 composite NP chemiresistive sensor: If the molar ratio of ZnO (smaller work function) to WO3 (larger work function) is larger than 1, the reducing gas-sensing properties of the ZnO NWs will be more significantly enhanced than the oxidizing gas-sensing properties. In contrast, if the molar ratio of ZnO to WO3 is smaller than 1, the oxidizing gas-sensing properties of the ZnO NWs will be more significantly enhanced than the reducing gas-sensing properties.ZnO and WO3 nanoparticles (NPs) were synthesized using sol-gel and hydrothermal methods, respectively. A 6:4 ZnO/WO3 composite NP chemiresistive sensor was prepared by adjusting the molar ratio of the ZnO and WO3 precursor solutions. The sensing test results for the sensor verified the feasibility of the hypothesis. The response of the 6:4 ZnO/WO3 NP composite sensor to 200-ppm CO was 39.7, which is the 2nd highest value reported to date. In addition, the undying sensing mechanism is discussed in detail.

One-pot three-component synthesis of α-amino nitriles using ZnO as a heterogeneous, reusable, and eco-friendly catalyst

Various forms of α-amino nitrile molecules are found to exert strong impacts on the synthesis of multiple organic compounds such as pharmaceuticals, amino acids, agrochemical agents, and pesticides. Spherical ZnO nanoparticles (NPs) prepared by a simple co-precipitation method are an efficient heterogeneous catalyst for the synthesis of vital intermediate α-amino nitriles. The present protocol was investigated via one-pot synthesis of α-amino nitriles over ZnO NPs using a three-component coupling reaction of aldehydes, amines, and trimethylsilyl cyanide in acetonitrile. The feasibility of our synthesis approach was assessed with respect to the purity and yield of synthesized products in relation to several controlling variables (e.g., ZnO molar ratio, reaction time, amines/aldehydes types, and solvent). The qualitative characteristics of α-amino nitrile products were evaluated by Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR), and mass spectroscopic analysis. A high yield (81–95%) of pure α-amino nitriles within a short reaction time (45–75 min) along with good recyclability of the catalyst (e.g., without significant loss in performance over five cycles) was confirmed as the distinctive merits of this new eco-friendly synthetic method. This study confirms that various amines including sterically crowded secondary amines should react efficiently with benzenoid plus non-benzenoid aldehyde to yield α-amino nitriles. The selected route is very fast as well as economical. Hence, this method can be used for large-scale production of a variety of biologically important molecules through α-amino nitriles.

Hydrothermal synthesis of multifunctional TiO2-ZnO oxide systems with desired antibacterial and photocatalytic properties

The aim of the study was the synthesis of multifunctional TiO2-ZnO oxide systems with desired antibacterial and photocatalytic activity. It was investigated how the TiO2:ZnO molar ratio and the time of hydrothermal treatment affected the physicochemical and structural properties (including morphology, crystalline and porous structure, as well as chemical surface composition) of the synthesized materials. For the first time this type of binary oxide systems were used as antibacterial materials against Gram-positive, Gram-negative and anaerobic bacteria. Moreover, the photocatalytic properties of the obtained materials were verified in the degradation of C.I. Basic Violet 10 dye. The SEM analysis demonstrates that binary oxide materials based on TiO2 and ZnO were found to have spherically and hexagonally shaped particles, characteristic of both oxides. The results of XRD, Raman and HRTEM analysis proved that the molar ratio of the components affects the crystalline structure of the synthesized oxide materials. Analysis of porous structure parameters showed that an increase in the ZnO content leads to a decrease in the BET surface area. Moreover, low-temperature N2 sorption analysis demonstrates that TiO2-ZnO oxide systems have higher surface are than the pure oxides. The TiO2-ZnO oxide systems exhibited very good antibacterial activity against Gram-positive bacteria, especially Staphylococcus aureus (including methicillin-resistant Staphylococcus aureus). The photo-oxidation tests proved that the binary oxide materials (especially the T9Zn1 samples) demonstrates high photocatalytic activity in the decomposition of C.I. Basic Violet 10 (95% after 180 min irradiation) compared with the reference titania sample.

Synthesis Photocatalytic TiO<sub>2</sub>/ZnO Nanocomposite and Investigation through Anatase, Wurtzite and ZnTiO<sub>3</sub> Phases Antibacterial Behaviors

Titanium dioxide is prepared by sol gel method from titanium tetraisopropoxide (TTIP) as precursor and likewise zinc oxide is prepared by sol gel method from zinc acetate dehydrate (ZAD) as precursor. The composite sols are prepared in three different molar ratios 90TiO2:10ZnO, 70TiO2:30ZnO and 50TiO2:50ZnO. Thin film deposition is carried out by dip coating technique. Crystal structure, surface morphology and photocatalytic activity of the prepared nanocomposite thin films are investigated. The antibacterial activity of the prepared nanocomposite thin film against E-coli ATCC 25922 bacteria is examined by placing the thin film in standard aqueous E-coli medium under UV light for 1, 2, 3 and 4 hours and then counting the bacteria with Standard Plate Count Agar (SPC) technique. The prepared thin films have shown strong antibacterial activity in the presence of UV light and by increasing the ZnO molar ratio from 10 to 50, antibacterial activity of the thin films decreases because of decreases in the anatase phase of the TiO2. In the dark conditions by increasing the molar ratio of ZnO, the antibacterial activity of the thin films increases and this phenomenon is related to increasing the zinc ions in the thin films.

Studying the effect of the controlled off-stoichiometry on the properties of Zn2SnO4 nanoparticles for DSSC applications

In this paper, the influence of off-stoichiometry and annealing temperature on the structural, electrical and optical properties of the zinc stannate nanoparticles prepared by conventional solid-state reaction method were studied. The structural studies revealed that the phase purity of the synthesized nanoparticles increases with annealing temperature. Furthermore, the reduction of the molar ratio of ZnO to SnO2 from 2 to 1.8 increased the electrical conductivity of the nanoparticles. The electrical conductivity improvement was ascribed to the excess Sn atoms in the nanoparticles which can fill the place of zinc atoms (Zn2+) or occupy interstitial sites in the zinc stannate lattice and lead to creation of more free electrons. Subsequently, the resultant nanoparticles were used as photoanode material. The fabricated dye-sensitized solar cells with 1.8 molar ratio of ZnO to SnO2 displayed better photovoltaic performance. Dye loading measurement on the Zn2SnO4-based photoelectrode revealed that the excess Sn in this structure not only increases the electrical conductivity of the Zn2SnO4 nanoparticles but also enhances their dye loading.

Fabrication of potassium salts doped zinc tungstates prepared with nitrate, sulfate, chloride and their photoluminescence properties

In this work, we found the significant improvement of photoluminescence of zinc tungstate doped with potassium salts. The samples were prepared by solid-state reaction using ZnO, WO3, KNO3, K2SO4, and KCl as starting powders. The powders were mixed with the molar ratios of ZnO: WO3: potassium salts = 1: 1: x and sintered at 800°C for 3h in air. The emission peak of photoluminescence excited at 275nm was observed at 465nm. With increasing potassium salts content, the intensity increased reached its maximum at x = 0.02 and decreased. The tendency of the luminescence intensity for KCl doping was almost the same as KNO3 doping, whereas, for K2SO4 doping, the tendency of the decrease was less steep than other doping. The order of each maximum intensity was KNO3>K2SO4>KCl. It was considered that K replacing Zn in the crystal lattice enhanced the intrinsic luminescence in the blue wavelength region. Moreover, different anions doping had the different effect of the enhancement of the luminescence.

Enhanced Dielectric Properties in Spark Plasma Sintered Zinc Titanate Ceramics

The ever increasing application of zinc titanate ceramics as a dielectric material in microwave devices and low temperature co-fired ceramics calls for the improvement in their dielectric properties. In this paper, the effect of different sintering techniques on the dielectric properties of zinc titanate have been discussed. Zinc titanate was prepared by ball milling 1:1 molar ratio of ZnO and TiO2 for 12 h and calcined at 800 °C for 2 h. The presence of ZnTiO3 and Zn2TiO4 phases were confirmed by X-ray diffraction and the dielectric properties of the sintered samples were studied using LCR meter. Samples consolidated by spark plasma sintering (SPS) showed highest densification (13% increase), higher dielectric permittivity (ɛr = 25.17) and Q factor (Q factor = 162.78) with lower loss tangent values (tanδ = 0.00614) than that of microwave sintered samples (ɛr = 21.86, Q factor = 99.08, tanδ = 0.01009) and conventionally sintered samples (ɛr = 20.54, Q factor = 60.07, tanδ = 0.01665). The fabrication time was considerably reduced for the materials prepared via SPS than that prepared by conventional route with improved properties and also the dependence of dielectric properties on density was confirmed in this research work.