Photocatalytic decomposition effect of erbium doped cerium oxide nanostructures driven by visible light irradiation: Investigation of cytotoxicity, antibacterial growth inhibition using catalyst.

Cerium (IV) oxide (CeO2) is the most accessible noble rare earth metal oxide for the excitation of the excitons by light-harvesting performance. The present work is focused on Erbium doped ceria nanoparticles that were beneficially obtained by hydrothermal method from cerium nitrate and Erbium nitrate as precursors for decomposition of Rhodamine-B (RhB) dye in the polluted waste water removed from the industries. Dye removal efficiency of the catalyst was found to be nearly ~94%. The structural phases, functional groups and the transitions are identified with the help of various techniques. XRD pattern determines the development of cubic phase with the particle size is 20 nm. Highly crystalline nature of as-synthesized nanomaterials with an average diameter of 35 nm was investigated by HRSEM. The crystalline size, shape and textural morphology, of the Erbium doped ceria nanostructures were analysed by HRTEM. Our results suggest, that the concentration of OH- ion determines the lattice constants and oxygen vacancy in the nanostructures which stimulate the probability of photocatalytic decomposition effect of organic pollutants, due to synergistic approach. In this context, both unhydrolyzed things and their swiftly drip from deceased or scratched cells with conceded membranes, even when the cells embrace some are outstanding attention. Although, the loss of viable cells also depends on epithelial cell dynamically conceal of numerous molar matrix.

Antibacterial, magnetic, optical and humidity sensor studies of ß-CoMoO4 - Co3O4 nanocomposites and its synthesis and characterization.

Cobalt Molybdate (ß-CoMoO4) and Cobalt Oxide (Co3O4) nanocomposite was prepared via co-precipitation and solid-state methods. Various techniques like powder XRD, FESEM, HRTEM, FTIR, VSM, UV-Vis and PL spectroscopy were used to investigate the structure and morphology of as prepared samples. Powder X-ray diffraction (XRD) reveals monoclinic and cubic structure for ß-CoMoO4 and Co3O4 respectively. The surface morphology was observed using field emission electron microscopy (FESEM) and high-resolution transmission electron microscopy (HRTEM), which shows the formation of nanocomposites at nanoscale range, the presence of elements were determined by energy dispersive x-ray spectroscopy (EDX). FTIR analysis confirms the formation and bonding nature of the samples. The anti-ferromagnetic behavior of CMCO64 composite was determined by vibrating sample magnetometer (VSM). The bandgap values were calculated by extrapolating the straight line on the energy axis (hν), and the values of ß-CoMoO4, CO3O4 and ß-CoMoO4 - CO3O4 composites were determined to be 2.20, 2.09 eV and 1.54-2.44 eV respectively. The weak blue emission peak observed at 489 nm is corresponds to crystal defects only observed in CMCO01 and CMCO64 composite, for CMCO10 the peak shifted to green region. Antibacterial studies illustrate good result for the CMCO64 composite against both Gram-negative and Gram-positive bacteria. The sensor studies were measured at different humidity environment (RH5% to RH98%). It was found that the increase in relative humidity leads to increase in the sensitivity factor of the samples. Among the samples CMCO64 composite possess highest sensitivity factor of (Sf = 4851) with response time of 60 s and recovery time of 230 s respectively.

Elucidation of photocatalysis, photoluminescence and antibacterial studies of ZnO thin films by spin coating method.

The ZnO thin films have been prepared by spin coating followed by annealing at different temperatures like 300°C, 350°C, 400°C, 450°C, 500°C & 550°C and ZnO nanoparticles have been used for photocatalytic and antibacterial applications. The morphological investigation and phase analysis of synthesized thin films well characterized by X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Photoluminescence (PL), Transmission Electron Microscopy (TEM) and Raman studies. The luminescence peaks detected in the noticeable region between 350nm to 550nm for all synthesized nanosamples are associated to the existence of defects of oxygen sites. The luminescence emission bands are observed at 487nm (blue emission), and 530nm (green emission) at the RT. It is observed that there are no modification positions of PL peaks in all ZnO nanoparticles. In the current attempt, the synthesized ZnO particles have been used photocatalytic and antibacterial applications. The antibacterial activity of characterized samples was regulated using different concentrations of synthesized ZnO particles (100µg/ml, 200µg/ml, 300µg/ml, 400µg/ml, 500µg/ml and 600µg/ml) against gram positive and gram negative bacteria (S. pnemoniae, S. aureus, E. coli and E. hermannii) using agar well diffusion assay. The increase in concentration, decrease in zone of inhibition. The prepared ZnO morphologies showed photocatalytic activity under the sunlight enhancing the degradation rate of Rhodamine-B (RhB), which is one of the common water pollutant released by textile and paper industries.

Facile synthesis of heterostructured cerium oxide/yttrium oxide nanocomposite in UV light induced photocatalytic degradation and catalytic reduction: Synergistic effect of antimicrobial studies.

Ceria (CeO2) is an exciting alternative noble metal catalyst, because it has ability to release and absorb oxygen in the redox system, and function as an oxygen buffer. In this study, heterostructured catalysts consisting of CeO2/Y2O3 nanocomposites were successfully synthesized by hydrothermal method in the presence of sodium hydroxide as a reducing agent from cerium nitrate and yttrium nitrate as a precursor which was then evaluated for its photocatalytic activity in the degradation of Rhodamine B (RhB) synthetic dye. Scanning electron microscopy (SEM) imparts the surface morphology and size of the prepared sample. Elemental compositions and the purity of the nanoparticles are proved by energy dispersive X-ray Spectroscopy (EDX). CeO2/Y2O3 nanoparticles were made up of CeO and YO bonds which are confirmed by Fourier transform infrared spectroscopy (FTIR). Synthesis temperature and pressure, during hydrothermal reactions, plays a critical role in controlling the shape, size, oxygen vacancy concentration, and low temperature reducibility in CeO2 based nanocomposites. The lattice constants and oxygen vacancy concentrations of ceria nanoparticles also depend upon the concentration of hydroxide ion which leads to better morphology at low temperature and pressure. Hydrogenation of p-nitrophenol to p-aminophenol with a reducing agent is conveniently carried out in aqueous medium by using this binary metal oxide catalyst. Further, the photocatalytic performance of the synthesized nanoparticles was monitored by photocatalytic degradation of Rhodamine B synthetic dye under UV light irradiation. To get maximum photocatalytic degradation (PCD) efficiency, we have used H2O2 for the generation of excess reactive oxygen species (ROS). In addition, the antibacterial activity of nanoparticles against bacteria was also examined. The observed antibacterial activity results are comparable with the results obtained using the standard antibiotic.

Antiproliferative effects on human lung cell lines A549 activity of cadmium selenide nanoparticles extracted from cytotoxic effects: Investigation of bio-electronic application.

Cadmium selenide (CdSe) nanoparticles make necessary to acquire more information against the cytotoxic effects on human lung epithelial cells A549 potential adverse to health effects. More biological studies highlighted their cytotoxic potential like pulmonary or respiratory diseases were focused on toxicity nanoparticles mechanisms are involved. The aim of our research, is the comparison of cytotoxicity effect between cells-particle interactions, viability test, membrane integrity and oxidative stress were investigated. XRD showed a strong peak associated with (111) plane of hexagonal CdSe suggesting formation of highly orientated nanoparticles. The longitudinal optical phonon shifted slightly due to strain whereas strong low-energy shoulder shift can be explained within a model for surface optical phonons. Photocatalytic activity of CdSe nanoparticles were investigated by exploiting photocatalytic degradation of Rhodamine B (RhB). The typical UV-vis absorption spectra of RhB solution at different time intervals it can be clearly seen that the relative intensity of the absorption peak corresponding to RhB, with the catalyst for different concentration time intervals (0mM, 2mM, 5mM & 10mM) of the prepared CdSe nanoparticles. After completion of 5mM % the dye was completely degraded and the absorption spectra act as a photocatalyst. CdSe nanoparticles exhibits antibacterial activity over a broad range of bacterial species and in particular against P. vulgaris where it out competes four other commonly used S. aureus, E.coli, P. vulgaris and E. hermannii, well as testing four different appropriate concentration from the results showed a significant gain in viable cell numbers of all four bacteria species, with 5mM and 10mM being the most effective and 2mM being the worst, where it provided only a slight improvement from the control in detail.

In vitro cytotoxicity effect and antibacterial performance of human lung epithelial cells A549 activity of Zinc oxide doped TiO2 nanocrystals: Investigation of bio-medical application by chemical method.

We report the synthesis of high quality ZnO doped TiO2 nanocrystals by chemical method at room temperature (RT), it can cause serious oxidative stress and DNA damage to human lung epithelial cells (A549) lines. Our aim in this study, to reduce the cytotoxicity effect of ZnO doped TiO2 nanocrystals are widely in biological fields. Several studies have been performed to understand the influence of ZnO doped titanium dioxide (TiO2-NPs) on cell function; however the effects of nanoparticle against to exposure on the cell membrane have been duly addressed fascinatingly so far. However, In this interaction, which may alter cell metabolism and integrity, it is one of the importance to understand the modifications of the cell membrane, mechanisms of pulmonary A549 cell lines nanoparticles were uptake and the molecular pathway during the initial cell responses are still unclear and much more investigative efforts are need to properly characterize the ZnO doped titanium dioxide nanoparticles were reported successfully. In particular of the epithelial cells, upon particles are exposed human pulmonary epithelial cells (A549) to various concentrations of composition, structure and morphology of the nanocrystals were analyzed by X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). XRD assessed the crystal structure of the nanocrystals which identified peaks associated with (002), (100) and (101) planes of hexagonal wurtzite-type ZnO with lattice constants of a=b=3.249Å and c=5.219Å. The IR results showed high purity of products and indicated that the nanocrystals are made up of TiO and ZnO bonds. The Photoluminescence (PL) spectra are dominated by a strong narrow band edge emission tunable in the blue region of the visible spectra indicating a narrow size distribution of ZnO/TiO2 nanocrystals which exhibits antibacterial activity over a broad range of bacterial species and in particular against Stre. Mut where it out competes four other commonly used E.coli, Pse. Aug, Stre. Mut and Salm. sps, well as testing four different appropriate concentration from the results showed a significant gain in viable cell numbers of all four bacteria species, with 5mM and 10mM being the most effective and 2mM being the worst, where it provided an effective improvement from the growth mechanism has been also proposed to the current interest of these nanocrystals will discussed in detail.

Photocatalytic degradation effect of malachite green and catalytic hydrogenation by UV-illuminated CeO2/CdO multilayered nanoplatelet arrays: Investigation of antifungal and antimicrobial activities.

CeO2/CdO multi-layered nanoplatelet arrays have been synthesized by sol-gel method at two different temperatures using Citrus limonum fruit extract and the effect of particle size on the photocatalytic performance is studied. The particle size and phases was analysed by X-ray diffraction pattern (XRD) which brought out the formation of cubic phase in the synthesized samples. Field Emission Scanning electron microscopy (FESEM) revealed the surface morphology and made up of cumulative form of platelet shaped arrays with an average size of 10nm. The elemental composition and the purity of the nanomaterials were confirmed by Energy Dispersive X-ray spectroscopy (EDX). CeO2/CdO multilayered binary metal oxide nanoplatelet arrays were formed which was further explored with Fourier transform infrared spectroscopy (FTIR), it reveals that the nanocomposites contain CeO and CdO bonds. Determination of the direct and indirect bandgap energy of the nanoplatelet arrays was carried out by UV-Vis-DRS studies. In MG degradation, both the hole (h+) and hydroxyl radical (OH) played a major role than the superoxide radical (O2-). Possible photo degradation mechanisms are proposed and discussed in this article. CeO2/CdO multi-layered nanoplatelet arrays showed antibacterial activity and among the tested ones, it showed better growth inhibition towards P. aeruginosa MTCC73. Thus, this greener synthetic procedure was a highly effective method due to low-cost, highly effective UV light responsive material for environmental safety.