p‐Block Bismuth Nanoclusters Sites Activated by Atomically Dispersed Bismuth for Tandem Boosting Electrocatalytic Hydrogen Peroxide Production.

Constructing electrocatalysts with p‐block elements is generally considered rather challenging owing to their closed d shells. Here for the first time, we present a p‐block‐element bismuth‐based (Bi‐based) catalyst with the co‐existence of single‐atomic Bi sites coordinated with oxygen (O) and sulfur (S) atoms and Bi nanoclusters (Biclu) (collectively denoted as BiOSSA/Biclu) for the highly selective oxygen reduction reaction (ORR) into hydrogen peroxide (H2O2). As a result, BiOSSA/Biclu gives a high H2O2 selectivity of 95 % in rotating ring‐disk electrode, and a large current density of 36 mA cm−2 at 0.15 V vs. RHE, a considerable H2O2 yield of 11.5 mg cm−2 h−1 with high H2O2 Faraday efficiency of ~90 % at 0.3 V vs. RHE and a long‐term durability of ~22 h in H‐cell test. Interestingly, the experimental data on site poisoning and theoretical calculations both revealed that, for BiOSSA/Biclu, the catalytic active sites are on the Bi clusters, which are further activated by the atomically dispersed Bi coordinated with O and S atoms. This work demonstrates a new synergistic tandem strategy for advanced p‐block‐element Bi catalysts featuring atomic‐level catalytic sites, and the great potential of rational material design for constructing highly active electrocatalysts based on p‐block metals. [ABSTRACT FROM AUTHOR]