Electrochemical CO2 reduction over nitrogen-doped SnO2 crystal surfaces

• 作 者: Yuefeng Zhang Jianjun Liu Zengxi Wei Quanhui Liu Caiyun Wang Jianmin Ma
• 机 构: School of Physics and Electronics, Hunan University, Changsha 410082, Hunan, China;ARC Centre of Exc
• 出 处: 能源化学
• 发表日期: 2019年6期
• 关键词: CO2 reduction reaction SnO2 Crystal surface Electrocatalysis First principles

Crystal planes of a catalyst play crucial role in determining the electrocatalytic performance for CO2 re-duction. The catalyst SnO2 can convert CO2 molecules into valuable formic acid (HCOOH). Incorporating heteroatom N into SnO2 further improves its catalytic activity. To understand the mechanism and real-ize a highly efficient CO2 -to-HCOOH conversion, we used density functional theory (DFT) to calculate the free energy of CO2 reduction reactions (CO2 RR) on different crystal planes of N-doped SnO2 (N-SnO2 ). The results indicate that N-SnO2 lowered the activation energy of intermediates leading to a better catalytic performance than pure SnO2 . We also discovered that the N-SnO2 (211) plane possesses the most suit-able free energy during the reduction process, exhibiting the best catalytic ability for the CO2 -to-HCOOH conversion. The intermediate of CO2 RR on N-SnO2 is HCOO or COOH instead of OCHO . These results may provide useful insights into the mechanism of CO2 RR, and promote the development of heteroatom-doped catalyst for efficient CO2 RR.