Kanica Anand

Synthesis, characterization, photocatalytic activity and ethanol-sensing properties of In2O3 and Eu3+:In2O3 nanoparticles

In the present endeavor, Indium oxide (In2O3) and Europium doped In2O3 (In2O3:0.5%Eu3+ and In2O3:5%Eu3+) nanoparticles were prepared by co-precipitation method. Synthesized nanoparticles were characterized using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and UV-Visible spectrophotometry (UV-vis). XRD revealed that nanoparticles were of pure bixbyite-type cubic phase and the crystallite size decreased with the Eu3+ doping. SEM micrographs showed that particles were spherical in shape. Synthesized nanoparticles were used for photo degradation of methylene blue (MB) dye under sunlight and the results clearly showed that In2O3:5%Eu3+ nanoparticles exhibited higher activity than pure In2O3 nanoparticles. For gas sensing characteristics, the nanoparticles were applied as thick film onto alumina substrate and tested at different operating temperatures. The results showed that the optimum operating temperature of the gas sensors prepared from synthesized nanoparticles is 300°C. The investigations...

Effect of pH on particles size and gas sensing properties of In2O3 nanoparticles

In this work, indium oxide (In2O3) nanoparticles have been synthesized by co-precipitation method and the effect of pH on the structural and sensor response values of In2O3 nanoparticles has been reported. X-ray diffraction pattern (XRD) revealed the formation of cubic phase In2O3 nanoparticles. FESEM results indicate the formation of nearly spherical shape In2O3 nanoparticles. The band gap energy value changed with change in pH value and found to have highest value at pH 9. Indium oxide nanoparticles thus prepared were deposited as thick films on alumina substrates to act as gas sensors and their sensing response to ethanol vapors and LPG at 50 ppm was investigated at different operating temperatures. It has been observed that all sensors exhibited optimum response at 300°C towards ethanol and at 400°C towards LPG. In2O3 nanoparticles prepared at pH 9, being smallest in size as compared to other, exhibit highest sensor response (SR).

Reduced graphene oxide/CeO2 nanocomposite with enhanced photocatalytic performance

In this work, reduced graphene oxide /cerium oxide (RGO/CeO2) nanocomposite was synthesized by in situ reduction of cerium nitrate Ce(NO3)3·6H2O in the presence of graphene oxide by hydrazine hydrate (N2H4.H2O). The intrinsic characteristics of as-prepared nanocomposite were studied using powder x-ray diffraction (XRD), Raman spectroscopy and field-emission scanning electron microscopy (FESEM). The photocatalytic degradation of methylene blue (MB) was employed as a model reaction to evaluate the photocatalytic activity of the RGO/CeO2 nanocomposite. The as-obtained RGO/CeO2 nanocomposite displays a significantly enhanced photocatalytic degradation of MB dye in comparison with bare CeO2 nanoparticles under sunlight irradiation, which can be attributed to the improved separation of electron-hole pairs and enhanced adsorption performance due to presence of RGO.

Structural, optical and ethanol gas sensing properties of In2O3 and Dy3+:In2O3 nanoparticles

This paper reports the structural, optical and ethanol gas sensing properties of In2O3 and 5% Dy3+doped In2O3 nanoparticles. The simple cost-effective hydrolysis assisted co-precipitation method was adopted. Synthesized samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-visible spectroscopy (UV-vis) techniques. XRD revealed that synthesized nanoparticles have cubic bixbyite phase. The lattice parameter, strain and crystallite size have been calculated by using the Williamson-Hall plots. UV-vis spectroscopy showed the red shift in the optical band gap due to Dy3+ doping in In2O3 nanoparticles. For ethanol gas sensing properties, the nanoparticles were applied as thick film onto alumina substrate and tested at different operating temperatures. The results showed that the optimum operating temperature of both the gas sensors is 300°C. At optimum operating temperature, the response of In2O3 and Dy3+:In2O3 gas sensor towards 250 ppm ethanol was found to be 9.65 and...