Exploring CO₂ electrochemical reduction mechanism on two-dimensional metal 2,3,6,7,10,11-triphenylenehexathiolate frameworks using density functional theory

Abstract

The reduction of CO₂ into valuable chemicals through electrocatalytic techniques provides a potential strategy to alleviate energy crises and environmental pollution. In this study, 2D M₃(THT)₂ (M = Fe, Co, Ni, Ru, Rh, Pd, THT = 2,3,6,7,10,11-triphenylenehexathiolate) framework as CO₂ reduction reaction (CO₂RR) electrocatalysts was investigated by using the density functional method. The results showed that the studied catalysts are stable both thermodynamically and electrochemically. Rh₃(THT)₂ exhibits the best catalytic performance to produce CH₄ with the overpotential of 0.61 V in the gas phase and 0.63 V in solution. The inactive hydrogen evolution reaction in Rh₃(THT)₂ would favour CO₂RR. For Fe₃(THT)₂ and Ru₃(THT)₂, the main product is CO. However, the strong CO adsorption on the catalyst surface can lead to catalyst to be poisoned, which makes Fe₃(THT)₂ and Ru₃(THT)₂ to be poor CO₂RR catalysts. We anticipate that this work may provide a new avenue for the development of high-performance 2D metal-organic framework-based electrocatalysts.

GRAPHICAL ABSTRACT

KEYWORDS:

• CO₂ reduction
• two-dimensional metal organic framework
• density functional study
• electroreduction
• reaction mechanism

Acknowledgements

This work is supported by The Local Scientific and Technological Development Plan guided by the Central Government (2021ZY0025), Program for Innovative Research Team in Universities of Inner Mongolia Autonomous Region (NMGIRT2214) and The Light of West China Program by Chinese Academy of Sciences. The computational time is supported by the computing center of Jilin Province and computing center of Changchun Institute of Applied Chemistry.

Disclosure statement

No potential conflict of interest was reported by the author(s).