Highly efficient electroreduction of CO2 to formate by nanorod@2D nanosheets SnO

• Published in: Journal of CO2 utilization 2020-12, Vol.42, p.101287, Article 101287
• Main Authors: Qian, Yao, Liu, Yifan, Tang, Hehua, Lin, Bo-Lin
• Format: Article
• Language: English
• Subjects: CO2 reduction reaction; Current density; Formate; Single-pass conversion; Tin monoxide
• ISSN: 2212-9820; 2212-9839
• DOI: 10.1016/j.jcou.2020.101287

[Display omitted] •The hierarchical NRS-SnO was designed to create a substantial number of exposed Sn(II) active sites in 2D nanosheets.•NRS-SnO enable the efficient reduction of CO2 to formate with high SPC and large current density.•This work should stimulate future research on improving CO2 utilization in GDE-based alkaline flow cell operating at industrially relevant current densities. Electrochemical carbon dioxide reduction reaction (CO2RR) is a key to achieving practical renewable energy conversion and storage as well as green chemical productions. Sn-based electrocatalysts are believed to be one of the most promising candidates for the electroreduction of CO2 to formate. However, development of novel catalysts operating at low overpotentials with a high selectivity, large current density and high single-pass conversion of CO2 (SPC) simultaneously remains a significant challenge. Here, we report a nanorod@sheet SnO (NRS-SnO) catalysts designed with abundant exposed Sn(II) active sites in the 2D nanosheets for high-performance electroreduction of CO2 to formate. Formate was first reliably detected at an applied potential as low as −0.2 V (vs. RHE) and reached maximum Faradaic Efficiency (FE) of ca. 94 % at −0.7 V (vs. RHE) with a partial current density (JHCOO-) of ca. −330 mA/cm2, giving the highest cathodic CO2-to-formate energy conversion efficiency (ca. 70 %) among known Sn catalysts for CO2RR to formate. Importantly, a high SPC of 39.3 % was achieved with the present system, proving for the first time that high SPC can be achieved for GDE based alkaline flow cell.