Synthesized ZrO2 Nanoparticles Research Articles

In-situ synthesized nanostructured t-ZrO2/La2(Zr0.75Ce0.25)2O7 composite thermal barrier coatings

As we all know, the poor toughness is an important factor that leads thermal barrier coatings to prematurely fail, which has been recognized as one of the urgent problems that need to be addressed. Herein, the nanostructured t-ZrO2/La2(Zr0.75Ce0.25)2O7 (LCZ) composite TBCs were constructed in-situ from plasma spraying. The microstructure and phase composition of nanostructured LCZ feedstocks and as-sprayed coatings were analysed. Moreover, the mechanism of in-situ synthesized nanostructured t-ZrO2/LCZ coatings was discussed in detail. Results show that as-sprayed coatings have the characteristics of bi-modal and dual-phase structures. The unmelted nanostructured LCZ feedstocks and in-situ synthesized ZrO2 nanoparticles are included in the nanostructured zone. The phase structure of coatings consists of fluorite LCZ and tetragonal ZrO2 (t-ZrO2). The presence of ZrO2 nanoparticles is derived from the decomposition of LCZ feedstocks during plasma spraying.

Antimicrobial Activity of Zirconium Oxide Nanoparticles Prepared by the Sol-Gel Method

The antimicrobial activity of zirconium oxide (ZrO2) nanoparticles on E.coli and S. aureus bacterial strains were investigated. The sol-gel method was used to fabricate zirconium oxide nanoparticles for two molar ratios (0.5 M and 1 M). The crystallinity and morphology of the product were confirmed using x-ray diffraction (XRD) was show that the prepared zirconium oxide has a crystalline nature. The FESEM analysis indicates that the NPs were less than 20 nm and highly uniformed in size, having spherical morphology. The FTIR confirms the production of reactive oxygen species (R.O.S.) in zirconium oxide. At doses equivalent to conventional antibiotics, ZrO2 nanoparticles were shown to exhibit antibacterial action against gram-positive (S. aureus) and gram-negative bacteria (E. coli). The synthesized ZrO2 nanoparticles demonstrated inhibitive activity against bacteria“ gram - ve E.coli by attracting negatively charged bacteria gram - ve E.coli, positively charged zirconium ions attack the cell wall. Results suggest that synthesized multifunctional ZrO2 nanoparticles may be a successful candidate in the health care system.

Zirconium oxide (ZrO2) nanoparticles from antibacterial activity to cytotoxicity: A next-generation of multifunctional nanoparticles

Health care costs of antibiotic resistance to the community have been astounding over the last decade and require urgent attention. This calls for new alternatives, such as metal oxide nanomaterials, to be considered at a more extended level. Metal oxide nanomaterials have been exerting a pull-on deal with its complete applications in biological and pharmaceutical fields of nanobiotechnology. The present study addresses the synthesis of nanoparticles of the zirconium oxide (ZrO2) by a process that can be quickly, economically and industrially used to combat deadly pathogens. The biological activity of synthesized zirconium oxide nanoparticles against bacterial strains has been studied by using agar well diffusion method. Besides, DPPH (1,1-diphenyl-2-picryl hydrazyl) and a nitrous oxide-scavenging study, we have also studied the antioxidant ability of ZrO2 nanoparticles along with the anticancer activity. Importantly, our research demonstrated the antimicrobial activity of ZrO2 nanoparticles at different concentrations comparable to standard antibiotics against gram-positive bacteria (Staphylococcus aureus) and gram-negative bacteria (Klebsiella pneumonia), respectively. We believe that the synthesized ZrO2 nanoparticles demonstrated inhibitive activity against K. pneumoniae by the attraction of negatively charged K. pneumoniae cell wall against positively charged zirconium ions. Our findings suggest that synthesized multifunctional ZrO2 nanoparticles may be a successful candidate in health care systems.

Size and Magnetic Effect of Manganese (Mn) Doped Zirconia (Zro2) Nanoparticles

Un-doped and different mol percentage of manganese doped zirconia nanoparticles were successfully synthesized via precipitation method. The size and magnetic properties of zirconia nanoparticles were systematically analyzed for different mol % manganese in ZrO2. Obtained results revealed that the manganese (Mn) concentrations played virtual role on various properties of the synthesized ZrO2 nanoparticles.

Zirconium oxide nanoparticle as an effective additive for non-damaging drilling fluid: A study through rheology and computational fluid dynamics investigation

The upsurge of drilling in shale and inaccessible reservoirs led to the emergence of Non Damaging Drilling Fluid (NDDF). Although this drilling fluid is non-invasive, the loss of rheological properties at high temperature poses a serious concern. In this study, we have investigated and quantified the enhancement in the performance of NDDF with the addition of zirconium oxide (ZrO2) nanoparticles (NPs) at 30, 60 and 80 °C. The synthesized ZrO2 NPs were of average 27 nm in size and were further characterized by Scanning Electron Microscope (SEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and Brunauer-Emmett-Teller (BET) adsorption methods. Varying concentrations, viz., 0.5, 0.8 and 1 wt% of ZrO2 NPs have been used to investigate their effect on various properties of NDDF. From the steady state rotational tests and viscoelastic measurements, it was observed that 1 wt% of ZrO2 NP NDDF had higher thermal stability in terms of viscosity and elasticity with a minimum filtrate loss. The ability to regain structural strength was also enhanced with the addition of ZrO2 NPs. Herschel Bulkley (HB) parameters from rheological measurements were calculated and optimized using genetic algorithm (GA) and were used to further carry out computational fluid dynamics (CFD) analysis. From CFD simulation results, it was observed that 1 wt% ZrO2 NP NDDF exhibited highest cutting carrying capacity as compared to 0 wt% (the base), 0.5 wt% and 0.8 wt% ZrO2 NP NDDF. Additionally, higher skewness in cutting deposition was observed for 1 wt% ZrO2 NP NDDF, limiting the possibility of bottom hole complications while drilling. This study is an important precursor for the oilfield application of nanoparticle based NDDF.

An ultrasensitive sensor based on polyoxometalate and zirconium dioxide nanocomposites hybrids material for simultaneous detection of toxic clenbuterol and ractopamine

A new electrochemical sensor based on isopolyacid anions (NH4)5PV8Mo4O40 (NPVMo) and transition metal zirconium dioxide (ZrO2) nanocomposites was prepared in double signal amplification for the simultaneous detection of clenbuterol (CLB) and ractopamine (RAC). This is the first time that ZrO2 was used as POM carrier to prepare electrochemical sensor. Scanning electron microscopic (SEM), nitrogen adsorption/desorption isotherms and X-ray diffraction (XRD) test showed that the synthesized ZrO2 nanoparticles have a needlelike nanostructure and a larger surface area. The electrochemical measurements such as cyclic voltammetry (CV), amperometric and differential pulse voltammetry (DPV) indicated that the NPVMo/ZrO2/GCE exhibited much high stability, fast response, good conductivity and electrocatalytic actives, which enhanced peak current and negatively shifted the oxidation potentials of CLB and RAC. Due to the synergistic action between NPVMo and ZrO2 nanoparticles, DPV results showed that the oxidation of CLB and RAC on NPVMo/ZrO2/GCE could be detected selectively and sensitively with low limits of detection, 5.03 × 10−9 mol L−1 for CLB and 9.3 × 10−7 mol L−1 for RAC, and a wide range for calibration curves of CLB and RAC from 0.1 to 1000 μM and 3.0 to 50 μM, respectively. In addition, the proposed sensor was applied to detect content of CLB and RAC in pork sample, and the recovery was over the range from 94.4 to 102.3%.

Performance of Concrete with Waste Tyre and Nano ZrO2

This paper presents the compressive strength of concrete which consists of 5% replacement of coarse aggregate with rubber aggregate, 25% replacement of cement with fly ash (Class C) and an additional amount of 0.2% of ZrO2 nanoparticles. The ZrO2 nanoparticles were synthesized using gel combustion technique where zirconium oxynitrate was used as the precursor and citric acid as the fuel in the molar ratio of 1:1.5 respectively. The synthesized ZrO2 nano particles were characterized using X-ray diffraction and the average crystallite size was found as 9.7 nm. Three types of mixes were taken into consideration; control mix (M40), rubber modified concrete mix and nano-rubber modified mix. The Scanning Electron Microscope imaging was done to study the morphology of the mixes. With the percentage of rubber aggregate replacement mentioned above there was found to be a considerable decrease in the compressive strength but on incorporation of nano ZrO2 along with rubber aggregate it was found out that there was an increase in compressive strength which even surpassed the strength of conventional concrete.

Effects of Oxidizing Media on the Composition, Morphology and Optical Properties of Colloidal Zirconium Oxide Nanoparticles Synthesized via Pulsed Laser Ablation in Liquid Technique.

In this work, pulsed laser ablation in liquid (PLAL) technique was applied to synthesize colloidal nanoparticles of zirconium oxide (ZrO2) in three different aqueous media (de-ionized water, ethanol and acetone). The structure, morphology, composition and optical properties of the synthesized nanoparticles were characterized by XRD, SEM, TEM, XPS, UV-Vis spectrophotometer and FT-IR analysis respectively. The structural analysis by XRD reveals the formation of mixture of monoclinic and tetragonal phases of nanocrystalline zirconia. The average crystallite sizes of ZrO2 by using Scherrer's formula were estimated to be 41.8, 42.6 and 40.3 nm in water, ethanol and acetone respectively for monoclinic phase while 20.1, 24.8 and 18.9 nm were for tetragonal phase of ZrO2 in water, ethanol and acetone respectively. Microstructure of our starting materials was confirmed from SEM analysis and morphology of the synthesized nanostructured ZrO2 was studied by TEM. TEM images show that the average particle size is less than 10 nm with spherical shapes. The XPS analysis reveals the elemental compositions of ZrO2 nanoparticles and their stoichiometric ratios. Optical properties of the synthesized ZrO2 nanoparticles were studied by UV-Vis absorption spectroscopy and Fourier transform infrared spectroscopy (FT-IR). Uv-Vis absorption spectroscopy revealed that the nanoparticle produced in water has higher absorption due to higher NPs concentrations suspended in water. The band gap of the synthesized ZrO2 nanoparticles in water, ethanol and acetone were estimated from Tauc's plot to be 5.19, 5.22 and 4.94 eV respectively. FT-IR analysis also ascertained the functional groups of ZrO2 nanoparticles in the three liquid media.

Sonocatalytic degradation of Reactive Yellow 39 using synthesized ZrO2 nanoparticles on biochar

ZrO2-biochar (ZrO2-BC) nanocomposite was prepared by a modified sonochemical/sol–gel method. The physicochemical properties of the prepared nanocomposite were evaluated using scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray fluorescence, Fourier transform infrared spectroscopy and Brunauer–Emmett–Teller model. The sonocatalytic performance of ZrO2-BC was investigated in sonochemical degradation of Reactive Yellow 39 (RY39). The high observed sonocatalytic activity of the ZrO2-BC sample could be interpreted by the mechanisms of sonoluminescence and hot spots. Parameters including ZrO2-BC dosage, solution pH, initial RY39 concentration and ultrasonic power were selected as the main operational parameters and their influence on RY39 degradation efficiency was examined. A 96.8% degradation efficiency was achieved with a ZrO2-BC dosage of 1.5g/L, pH of 6, initial RY39 concentration of 20mg/L and ultrasonic power of 300W. In the presence of OH radical scavengers, RY39 degradation was significantly inhibited, providing evidence for the key role of hydroxyl radicals in the process. The sonodegradation intermediates were identified using gas chromatography-mass spectroscopy and the possible decomposition route was proposed.

Improving the sonocatalytic performance of good crystallinity ZrO2 nanocomposite through graphene addition

In this study, the catalytic performance of the ZrO2 nanoparticles is enhanced by combining ultrasonic radiation with graphene material addition. The structural, morphological and surface properties of sol-gel synthesized ZrO2 nanoparticles with three different annealing temperatures (350°C, 550°C, and 750°C) were investigated using various characterization methods, including X-Ray Diffraction, Transmission Electron Microscope measurements and Brunauer-Emmett-Teller measurements. The result show that if the annealing process does not take place, ZrO2 nanoparticles have an amorphous structure. The formation of the crystalline structures of the tetragonal phase of the nanoparticle begins at an annealing temperature of 550°C. The highest sonocatalytic performance of nanoparticles is achieved at an annealing temperature of 550°C. The ZrO2/graphene nanocomposites were produced via co-precipitation methods at all annealing temperatures. The sonocatalytic activities in the presence of ZrO2/graphene nanocomposite indicate an enhancement, compared with ZrO2 nanoparticles. ZrO2 with and without graphene composites shows a level of stability that would allow reuse. A reasonable catalysis mechanism of ZrO2 with and without graphene composites is proposed.

Influence of the oxygen concentration on the formation of crystalline phases of ZrO2 nanoparticles during the low-pressure arc-discharge plasma synthesis

The synthesis of nanoparticles of zirconium dioxide with different contents of the monoclinic and tetragonal phases has been investigated. The synthesis has been performed by controlling the oxygen content in the gas mixture in the plasma-chemical evaporation–condensation process in low-pressure arc-discharge plasma. The crystal structure of synthesized ZrO2 nanoparticles has been studied using X-ray diffraction. The morphology of the particles has been analyzed using transmission electron microscopy. The nanoparticle growth in arc-discharge plasma has been examined using optical emission spectroscopy. The X-ray powder diffraction analysis has revealed that the content of the monoclinic phase of ZrO2 increases with a decrease in the oxygen content in the oxygen–argon gas mixture.

Influence of crystal structure of nanosized ZrO2 on photocatalytic degradation of methyl orange.

Nanosized ZrO2 powders with near pure monoclinic, tetragonal, and cubic structures synthesized by various methods were used as catalysts for photocatalytic degradation of methyl orange. The structural and textural properties of the samples were analyzed by X-ray diffraction, Raman spectroscopy, TEM, UV-vis, X-ray photoelectron spectroscopy (XPS), and N2 adsorption measurements. The performance of synthesized ZrO2 nanoparticles in the photocatalytic degradation of methyl orange under UV light irradiation was evaluated. The photocatalytic activity of the pure monoclinic ZrO2 sample is higher than that of the tetragonal and cubic ZrO2 samples under optimum identical conditions. The characterization results revealed that monoclinic ZrO2 nanoparticles possessed high crystallinity and mesopores with diameter of 100 Å. The higher activity of the monoclinic ZrO2 sample for the photocatalytic degradation of methyl orange can be attributed to the combining effects of factors including the presence of small amount of oxygen-deficient zirconium oxide phase, high crystallinity, large pores, and high density of surface hydroxyl groups.