ZnO-In2O3 nanocomposite: An efficient solar photocatalyst

Abstract

Semiconductor photocatalysis is one of the most promising technology to address energy and environmental issues in a self-sustainable manner. Among different semiconductor photocatalysts, Zinc Oxide (ZnO) is one of the most studied photocatalyst. However, the photoactivity of ZnO is limited due to photon absorption in UV range and high charge carrier recombination. Considering the above, the current work report the synthesis of ZnO-In2O3 nanocomposite as an efficient photocatalyst through hydrothermal process. The structural, surface, elemental and optical properties of the samples were evaluated using various characterization methods such as X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), energy dispersive X-ray spectroscopy (EDS) and UV-Vis analyses. XRD spectra reveals the high crystallinity of samples with crystallite size distribution in nano range. The FESEM micrographs of the pristine and composite material exhibit nanodisc like structure. An increase in crystallite size is observed for composite material compared to the pristine one and it is in accordance with the XRD results. The absorbance spectra of the composite material shows an elevated redshift towards visible region. Moreover, EDS, XRD and UV-Vis spectra confirms the formation ZnO-In2O3 nanocomposite. Photocatalytic performance of the samples were evaluated under solar irradiation using methylene blue as a probe pollutant. The ZnO-In2O3 showed superior photocatalytic performance in terms of rate constant and photonic efficiency compared to pristine one. The enhanced photocatalytic performance of the ZnO-In2O3 nanocomposite may be attributed to the enhanced photon absorption in visible range and effective charge carrier separation at the composite interface. However more studies are required to confirm the same.