Investigating the Electrochemical reduction of Co2 at metal sulfides

Abstract

Electrochemical reduction of CO2 and CO has attracted great interests for both economic and scientific reasons. The purpose of this project is to study the possibility and mechanism of the cathodic reduction of CO2 and CO at metal sulfides.The current work consists of two parts. In the first part the process of electrochemical synthesis of FeS has been studied using voltammetic technique. The optimal condition for the preparation of FeS was found to be pH11 and -0.5V(NHE).In the second part, the mechanism of CO2 electroreduction at FeS and FeS2 has been investigated utilizing cyclic voltammetry and in situ surface enhanced Raman spectroscopy. This is the first study of CO2/CO reduction at semiconductors rather than metals. By comparing the data obtained from N2, CO and CO2 saturated electrolytes, the formation of adsorbed CO has been proposed to be the elemental step during the electroreduction of CO2 at metal sulfides.