title: Rational Design of a Hierarchical Tin Dendrite Electrode for Efficient Electrochemical Reduction of CO2.
abstract: Catalysis is a key technology for the synthesis of renewable fuels through electrochemical reduction of CO2 . However, successful CO2 reduction still suffers from the lack of affordable catalyst design and understanding the factors governing catalysis. Herein, we demonstrate that the CO2 conversion selectivity on Sn (or SnOx /Sn) electrodes is correlated to the native oxygen content at the subsurface. Electrochemical analyses show that the reduced Sn electrode with abundant oxygen species effectively stabilizes a CO2 (.-) intermediate rather than the clean Sn surface, and consequently results in enhanced formate production in the CO2 reduction. Based on this design strategy, a hierarchical Sn dendrite electrode with high oxygen content, consisting of a multi-branched conifer-like structure with an enlarged surface area, was synthesized. The electrode exhibits a superior formate production rate (228.6 μmol h(-1)  cm(-2) ) at -1.36 VRHE without any considerable catalytic degradation over 18 h of operation.
authors.affiliation: Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Republic of Korea).
authors.forename: Da Hye
authors.initials: da H
authors.lastname: Won
authors.affiliation: Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Republic of Korea).
authors.forename: Chang Hyuck
authors.initials: CH
authors.lastname: Choi
authors.affiliation: Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Republic of Korea).
authors.forename: Jaehoon
authors.initials: J
authors.lastname: Chung
authors.affiliation: Graduate School of EEWS (BK21PLUS), Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Republic of Korea).
authors.forename: Min Wook
authors.initials: MW
authors.lastname: Chung
authors.affiliation: Protein Structure Research Team, Korea Basic Science Institute, Cheongjoo 363-663 (Republic of Korea).
authors.forename: Eun-Hee
authors.initials: EH
authors.lastname: Kim
authors.affiliation: Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Republic of Korea). siwoo@kaist.ac.kr.|Graduate School of EEWS (BK21PLUS), Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Republic of Korea). siwoo@kaist.ac.kr.
authors.forename: Seong Ihl
authors.initials: SI
authors.lastname: Woo
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry; D002384:Catalysis; D015195:Drug Design; D004563:Electrochemistry / Q000295:instrumentation*; D004566:Electrodes; D005561:Formates / Q000737:chemistry; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry; D014001:Tin / Q000737:chemistry*
chemical_list: D005561:Formates; C030544:formic acid; D002245:Carbon Dioxide; D014001:Tin; D010100:Oxygen
keywords: carbon dioxide; electrocatalysis; formate; oxygen content; tin