Bi(OH)₃/PdBi Composite Nanochains as Highly Active and Durable Electrocatalysts for Ethanol Oxidation

Developing high-performance electrocatalysts for the ethanol oxidation reaction (EOR) is critical to the commercialization of direct ethanol fuel cells. However, current EOR catalysts suffer from high cost, low activity, and poor durability. Here we report the preparation of PdBi-Bi­(OH)₃ composite nanochains with outstanding EOR activity and durability. The incorporation of Bi can tune the electronic structure and downshift the d-band center of Pd while the surface decoration of Bi­(OH)₃ can facilitate the oxidative removal of CO and other carbonaceous intermediates. As a result, the nanochains manifest an exceptional mass activity (5.30 A mg_Pd^–1, 4.6-fold higher than that of commercial Pd/C) and outstanding durability (with a retained current density of ∼1.00 A mg_Pd^–1 after operating for 20 000 s). More importantly, the nanochain catalyst can be reactivated, and negligible activity loss has been observed after operating for 200 000 s with periodic reactivation, making it one of the best EOR catalysts.