In-Situ Investigation of Surface Modifiers Dithiocarbamates on Au Electrodes for Electrochemical CO2 Reduction

Abstract

Molecular functionalization of metal electrodes via self-assembled monolayers (SAMs) can introduce synthetically tunable properties to metal surfaces and has exhibited great potential in electrocatalysis. Alkanethiols are commonly used organic ligands because of their strong affinity to Au but they are prone to desorption at negative potentials. Alternatively, dithiocarbamates (DTC) show superior electrochemical stability. In this study, a series of DTCs, differing in hydrophobicity, size, and steric bulk, were synthesized to prepare SAM-functionalized Au electrodes. The properties of the resulting surfaces (e.g. wettability, surface coverage, and reductive stability) were investigated by analytical and electrochemical techniques. Particularly, in-situ approaches such as surface-enhanced infrared absorption spectroscopy (SEIRAS) are employed to characterize the molecularly modified interface. The novel catalyst platforms were explored for electrochemical CO2 reduction.