In-situ DRIFT investigation of photocatalytic reduction and oxidation properties of SiO2@α-Fe2O3 core-shell decorated RGO nanocomposite

Uma Kasimayan; Arjun Nadarajan; Chandra Mohan Singaravelu; Guan-Ting Pan; Jothivenkatachalam Kandasamy; Thomas C-K Yang; Ja-Hon Lin

doi:10.1038/s41598-020-59037-9

In-situ DRIFT investigation of photocatalytic reduction and oxidation properties of SiO₂@α-Fe₂O₃ core-shell decorated RGO nanocomposite

Sci Rep. 2020 Feb 7;10(1):2128. doi: 10.1038/s41598-020-59037-9.

Authors

Uma Kasimayan¹, Arjun Nadarajan², Chandra Mohan Singaravelu³, Guan-Ting Pan², Jothivenkatachalam Kandasamy³, Thomas C-K Yang⁴, Ja-Hon Lin⁵

Affiliations

¹ Department of Electro-Optical Engineering, National Taipei University of Technology, Taipei, Taiwan, 106.
² Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei, Taiwan, 106.
³ Department of Chemistry, Anna University, BIT Campus, Tiruchirappalli, 620024, Tamil Nadu, India.
⁴ Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei, Taiwan, 106. ckyang@mail.ntut.edu.tw.
⁵ Department of Electro-Optical Engineering, National Taipei University of Technology, Taipei, Taiwan, 106. jhlin@ntut.edu.tw.

Abstract

In this work, SiO₂@α-Fe₂O₃ 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 SiO₂@α-Fe₂O₃ 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 CO₂ and oxidation of ethanol using in-situ diffuse-reflectance infrared fourier transform spectroscopy (DRIFT). The prepared nanocomposite with (30 wt %) of SiO₂@α-Fe₂O₃ showed superior photocatalytic activity for the gas phase reduction of CO₂ 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 CO₂ and oxidation of ethanol. Further, the evaluation of photoelectrochemical CO₂ 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 %)-SiO₂@α-Fe₂O₃ nanocomposite.