Metalloporphyrin decorated rGO-TiO2 composite for understanding electrochemical properties towards CO2 reduction

Abstract

Carbon dioxide (CO2) significantly contributes to global warming and climate change. The excessive burning of fossil fuels to fulfil almost 80% of global energy demand is largely responsible for CO2 emission. To alleviate the negative impact of CO2 discharge, many researchers are exploring ways to convert CO2 into value-added hydrocarbon (HC) fuels as an efficient solution for diminishing greenhouse gas emissions and developing sustainable sources of renewable energy. CO2 electroreduction is a promising technology that involves the use of an electrocatalyst, that can facilitate the electrochemical reduction of CO2 into green products that can provide a pathway towards a circular carbon economy. This study focuses on synthesizing beneficial nano hybrid electrocatalysts and analysing their electrocatalytic properties for the effective electrochemical reduction of CO2. Herein, metalloporphyrin is incorporated as a molecular cocatalyst with the TiO2 (P25) and rGO (reduced graphene oxide) composite to enhance the electron transfer kinetics and electrochemical reduction activity of CO2. This trio of GO-TiO2 /metalloporphyrin catalysts was synthesized by performing the solvothermal process. The characterizations of the catalyst composites are analysed by performing several instrumental techniques such as Fourier-transform infrared (FTIR) spectroscopy, Raman spectroscopy, Thermogravimetric analysis (TGA), UV-visible spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) techniques. These spectroscopic techniques have provided valuable insights into the structure, morphology, and composition of the composite material. The electrochemical reduction performance of the prepared catalysts was assessed by performing cyclic voltammetry with rGO-TiO2/TAPP, rGO-TiO2/ Zn-TAPP and rGO-TiO2/Ni-TAPP nano electrocatalyst coated on glassy carbon (GC) electrode.