Computational study of electrochemical CO2 reduction on two-dimensional TiB2 monolayer

Abstract

The production of organic molecules from CO2 is extremely desirable from both an energy and environmental standpoint. High-performance catalysts are necessary to accomplish such a desirable outcome. In this study, CO2 reducion reaction (CO2RR) pathways to formic acid, methanol, and CH4 are investigated over a two-dimensional transition metal diboride TiB2 using DFT calculations combined with the hydrogen electrode model. Analysis of the adsorption configurations and electronic structures demonstrated that CO2 could be chemically adsorbed on the Tis side of TiB2 with an adsorption energy of −2.47 eV. Further, our study revealed that the TiB2 enabled CO2RR to proceed through multiple electron paths to produce HCOOH and CH3OH with limiting potentials of 1.11 eV and 1.20 eV, respectively. Additionally, CO2RR via the two-electron pathway would result in HCOOH along the COOH pathway rather than CO with a comparatively low ΔG of −0.42 eV. Our research might open up new avenues for the electrocatalytic CO2 reduction applications of 2D metal diborides.