In-situ DRIFT investigation of photocatalytic reduction and oxidation properties of SiO2@α-Fe2O3 core-shell decorated RGO nanocomposite
Kasimayan Uma, Nadarajan Arjun, Singaravelu Chandra Mohan, Guan‐Ting Pan, Kandasamy Jothivenkatachalam, Thomas C.‐K. Yang, Ja‐Hon Lin
Abstract
Abstract In this work, SiO 2 @α-Fe 2 O 3 core-shell decorated RGO nanocomposites were prepared via a simple sol-gel method. The nanocomposites were prepared with different weight percentages (10, 30, and 50 wt %) of the SiO 2 @α-Fe 2 O 3 core-shell on RGO, and the effects on the structural and optical properties were identified. The photocatalytic reduction and oxidation properties of the nanocomposites in the gas phase were assessed through the reduction of CO 2 and oxidation of ethanol using in-situ diffuse-reflectance infrared fourier transform spectroscopy (DRIFT). The prepared nanocomposite with (30 wt %) of SiO 2 @α-Fe 2 O 3 showed superior photocatalytic activity for the gas phase reduction of CO 2 and oxidation of ethanol. Enhancement in the activity was also perceived when the light irradiation was coupled with thermal treatment. The DRIFT results for the nanocomposites indicate the active chemical conversion kinetics of the redox catalytic effect in the reduction of CO 2 and oxidation of ethanol. Further, the evaluation of photoelectrochemical CO 2 reduction performance of nanocomposites was acquired by linear sweep voltammetry (LSV), and the results showed a significant improvement in the onset-potential (–0.58 V) for the RGO (30 wt %)-SiO 2 @α-Fe 2 O 3 nanocomposite.