Atomically dispersed Lewis acid sites boost 2-electron oxygen reduction activity of carbon-based catalysts.

ABSTRACT: Elucidating the structure-property relationship is crucial for the design of advanced electrocatalysts towards the production of hydrogen peroxide (H₂O₂). In this work, we theoretically and experimentally discovered that atomically dispersed Lewis acid sites (octahedral M-O species, M?=?aluminum (Al), gallium (Ga)) regulate the electronic structure of adjacent carbon catalyst sites. Density functional theory calculation predicts that the octahedral M-O with strong Lewis acidity regulates the electronic distribution of the adjacent carbon site and thus optimizes the adsorption and desorption strength of reaction intermediate (*OOH). Experimentally, the optimal catalyst (oxygen-rich carbon with atomically dispersed Al, denoted as O-C(Al)) with the strongest Lewis acidity exhibited excellent onset potential (0.822 and 0.526?V versus reversible hydrogen electrode at 0.1?mA?cm^-2 H₂O₂ current in alkaline and neutral media, respectively) and high H₂O₂ selectivity over a wide voltage range. This study provides a highly efficient and low-cost electrocatalyst for electrochemical H₂O₂ production.

SUBMITTER: Yang Q 

PROVIDER: S-EPMC7603490 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature