Oxygen Functional Groups Regulate Cobalt‐Porphyrin Molecular Electrocatalyst for Acidic H2O2 Electrosynthesis at Industrial‐Level Current

• Published in: Angewandte Chemie International Edition Vol. 63; no. 34; pp. e202407163 - n/a
• Main Authors: Chen, Yihe, Zhen, Cheng, Chen, Yubin, Zhao, Hao, Wang, Yuda, Yue, Zhouying, Wang, Qiansen, Li, Jun, Gu, M. Danny, Cheng, Qingqing, Yang, Hui
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 19.08.2024
• Edition: International ed. in English
• Subjects: Acidic oxides; Aqueous solutions; Catalysts; Cobalt; Electrocatalysts; Electronic structure; Functional groups; Graphene; H2O2 electrosynthesis; Hydrogen peroxide; Local-environmental regulation; Molecular electrocatalyst; Molecular structure; Oxygen; Oxygen functional groups; PEM electrolyzer; Porphyrins; Raman spectroscopy; Spectroscopy; Spectrum analysis
• ISSN: 1433-7851; 1521-3773; 1521-3773
• DOI: 10.1002/anie.202407163

Electrosynthesis of hydrogen peroxide (H2O2) based on proton exchange membrane (PEM) reactor represents a promising approach to industrial‐level H2O2 production, while it is hampered by the lack of high‐efficiency electrocatalysts in acidic medium. Herein, we present a strategy for the specific oxygen functional group (OFG) regulation to promote the H2O2 selectivity up to 92 % in acid on cobalt‐porphyrin molecular assembled with reduced graphene oxide. In situ X‐ray adsorption spectroscopy, in situ Raman spectroscopy and Kelvin probe force microscopy combined with theoretical calculation unravel that different OFGs exert distinctive regulation effects on the electronic structure of Co center through either remote (carboxyl and epoxy) or vicinal (hydroxyl) interaction manners, thus leading to the opposite influences on the promotion in 2e− ORR selectivity. As a consequence, the PEM electrolyzer integrated with the optimized catalyst can continuously and stably produce the high‐concentration of ca. 7 wt % pure H2O2 aqueous solution at 400 mA cm−2 over 200 h with a cell voltage as low as ca. 2.1 V, suggesting the application potential in industrial‐scale H2O2 electrosynthesis. A local‐environmental regulation infinitely clarifies distinguishing interaction manners (remote or vicinal interaction) between different oxygen functional groups and Co center, and hence enhances the acidic H2O2 electrosynthesis on cobalt‐porphyrin molecular catalyst.