Insights into electrochemical CO2 reduction on tin oxides from first-principles calculations

• 作者: Hongliang Xin Jiamin Wang Siwen Wang
• 来源期刊: 绿色能源与环境：英文版
• 学科: 化学
• 年，卷（期）: 2017,（2）
• 页码范围: 168-171
• 页数: 4页
• 分类号: O643.32

摘要

Density functional theory calculations were used to unravel the mechanism of CO2 electroreduction on SnOx surfaces. Under highly reducing conditions（<-0.6 V vs. RHE）, the SnO（101） surface with oxygen vacancies is likely the active phase for CO2 reduction. We showed that the proton-electron transfer to adsorbed *CO2 forming *OCHO, a key intermediate for producing HCOOH, is energetically more favorable than the formation of *COOH, justifying the selectivity trends observed on Sn-based electrocatalysts. With linear scaling relations, we propose the free formation energy of *CO2 at the oxygen vacancy as the reactivity descriptor. By engineering the strain of the SnO（101） surface, the selectivity towards HCOOH can be further optimized at reduced overpotentials.