Facile CO2 Electro-Reduction to Formate via Oxygen Bidentate Intermediate Stabilized by High-Index Planes of Bi Dendrite Catalyst

• Published in: ACS catalysis 2017-08, Vol.7 (8), p.5071-5077
• Main Authors: Koh, Jai Hyun, Won, Da Hye, Eom, Taedaehyeong, Kim, Nak-Kyoon, Jung, Kwang Deog, Kim, Hyungjun, Hwang, Yun Jeong, Min, Byoung Koun
• Format: Article
• Language: English
• ISSN: 2155-5435; 2155-5435
• DOI: 10.1021/acscatal.7b00707

Electrochemical CO2 conversion to chemical products is a promising strategy for sustainable industrial development. However, the success of this approach requires an in-depth understanding of catalysis because it involves highly complex multistep reactions. Herein, we suggest a rational design of a hierarchical Bi dendrite catalyst for an efficient conversion of CO2 to formate. A high selectivity (∼89% at −0.74 VRHE) and, more importantly, a stable performance during long-term operation (∼12 h) were achieved with the Bi dendrite. Density functional theory (DFT) is used to investigate three possible reaction pathways in terms of surface intermediate, and the one via *OCOH surface intermediate is calculated to be the most energetically feasible. DFT calculations further elucidate the plane-dependent catalytic activity and conclude that the high-index planes developed on the Bi dendrite are responsible for the sustainable performance of Bi dendrite. We expect that our experimental and theoretical study will provide a fundamental guideline for the CO2-to-formate conversion pathway as well as design principles for enhancing the catalytic performance.