Impact of Pore Structure on Two‐Electron Oxygen Reduction Reaction in Nitrogen‐Doped Carbon Materials: Rotating Ring‐Disk Electrode vs. Flow Cell. Issue 5 (31st January 2022)

• Record Type: Journal Article
• Authors: Xu, Hui; Lv, Xue‐Hui; Wang, Hao‐Yu; Ye, Jin‐Yu; Yuan, Jiayin; Wang, Yu‐Cheng; Zhou, Zhi‐You; Sun, Shi‐Gang
• Is Part Of: ChemSusChem. Volume 15:Issue 5(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-01-31
• Subjects: electrocatalysis -- electrosynthesis -- hydrogen peroxide -- oxygen reduction reaction -- porous materials; Green chemistry -- Periodicals; Sustainable engineering -- Periodicals; Chemistry -- Periodicals; Chemical engineering -- Periodicals; 660
• DOI: 10.1002/cssc.202102587
• Languages: English
• ISSNs: 1864-5631

Abstract

Abstract: The impact of pore structure on the two‐electron oxygen reduction reaction (ORR) in nitrogen‐doped carbon materials is currently under debate, and previous studies are mainly limited to the rotating ring‐disk electrode (RRDE) rather than the practical flow cell (FC) system. In this study, assisted by a group of reliable pore models, the impact of two pore structure parameters, that is, Brunauer–Emmett–Teller surface area ( S BET ) and micropore surface fraction ( f micro ), on ORR activity and selectivity are investigated in both RRDE and FC. The ORR mass activity correlates positively to the S BET in the RRDE and FC because a higher S BET can host more active sites. The H2 O2 selectivity is independent of f micro in the RRDE but correlates negatively to f micro in the FC. The inconsistency results from different states of the electrode in the RRDE and the FC. These insights will guide the design of carbon materials for H2 O2 synthesis. Abstract : A pore excuse for selectivity : The two‐electron oxygen reduction reaction (ORR) selectivity is independent of the micropore surface fraction ( f micro ) in a rotating ring‐disk electrode (RRDE) but correlates negatively to f micro in a flow cell (FC). The inconsistency results from the different reaction microenvironments in the RRDE to and the FC.