Investigation of a Novel Rhenium Disulfide Electrocatalyst By Sum Frequency Generation Vibrational Spectroscopy

Abstract

The heterogeneous electrocatalysis is developing as a promising approach to overcome the energy regeneration issues around the world. It is well known for the enhancement of stability, selectivity, and productivity for the catalytic reaction, especially in the electrocatalytic reaction. By binding electrocatalytic molecules onto the metal or semiconductor electrode surface, CO2 reduction reaction or H2 evolution reaction can be more efficient. However, the behaviors of catalysts during heterogeneous electrocatalysis are always triggering people’s interest in understanding how interfacial electric field interacts with molecules. In this paper, a novel rhenium -based CO2 reduction electrocatalyst Re(SSbpy)(CO)3Cl was synthesized and attached to polycrystalline gold film electrode. By probing the symmetric CO stretching mode with potential dependent SFG vibrational spectroscopy, the Stark shifting rate of 7~8 cm-1/V under applied bias was revealed, indicating a weak correlation between symmetric CO stretching dipole and interfacial electric field. In addition, DFT calculation represented that this molecule tended to be adsorbed on the gold surface with nearly zero tilt angle with a great agreement to spectroscopic results.