Bifunctional effect of Bi(OH)3 on the PdBi surface as interfacial Brønsted base enables ethanol electro-oxidization

Palladium (Pd) is supposed to be one of the most promising catalytic metals towards ethanol (C 2 H 5 OH) oxidation reaction (EOR). However, Pd electrocatalysts easily suffer from the poisoning of the intermediates (especially CO), resulting in the quick decay of EOR catalysis. Herein, inspired by the Brønsted-Lowry acid-base theory, a “attraction–repulsion” concept is proposed to guide the surface structure engineering toward EOR catalysts. Specifically, we induce Bi(OH) 3 species as Brønsted base onto PdBi nanoplates to effectively repel the adsorption of CO intermediates. The PdBi-Bi(OH) 3 nanoplates show an impressive mass activity of 4.46 A mg Pd -1 during the EOR catalysis and keep excellent stability. Both the stability and enhanced performance are attributed by the interfacial Brønsted base Bi(OH) 3 which can selectively attract and repel reactants and intermediates, as evidenced from in situ measurements and theoretical views.