Ordered Ag Nanoneedle Arrays with Enhanced Electrocatalytic CO2 Reduction via Structure-Induced Inhibition of Hydrogen Evolution

Chen, Qin; Liu, Kang; Zhou, Yajiao; Wang, Xiqing; Wu, Kuangzhe; Li, Hongmei; Pensa, Evangelina; Fu, Junwei; Miyauchi, Masahiro; Cortes, Emiliano und Liu, Min (2022): Ordered Ag Nanoneedle Arrays with Enhanced Electrocatalytic CO2 Reduction via Structure-Induced Inhibition of Hydrogen Evolution. In: Nano Letters, Bd. 22, Nr. 15: S. 6276-6284

Abstract

Silver is an attractive catalyst for converting CO2 into CO. However, the high CO2 activation barrier and the hydrogen evolution side reaction seriously limit its practical application and industrial perspective. Here, an ordered Ag nanoneedle array (Ag-NNAs) was prepared by template-assisted vacuum thermal-evaporation for CO2 electroreduction into CO. The nanoneedle array structure induces a strong local electric field at the tips, which not only reduces the activation barrier for CO2 electroreduction but also increases the energy barrier for the hydrogen evolution reaction (HER). Moreover, the array structure endows a high surface hydrophobicity, which can regulate the adsorption of water molecules at the interface and thus dynamically inhibit the competitive HER. As a result, the optimal Ag-NNAs exhibits 91.4% Faradaic efficiency (FE) of CO for over 700 min at -1.0 V vs RHE. This work provides a new concept for the application of nanoneedle array structures in electrocatalytic CO2 reduction reactions.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik
• ISSN: 1530-6984
• Sprache: Englisch
• DFG: Gefördert durch die Deutsche Forschungsgemeinschaft (DFG) - 390776260