In situ confined synthesis of an interlayer-riveted carbon shell encapsulated PdZnBi alloy as a highly active and durable oxygen reduction reaction catalyst

Abstract

Stability has always been the main limiting problem for developing oxygen reduction reaction (ORR) catalysts practically. A PdZnBi alloy ORR catalyst with an interlayer-riveted carbon shell encapsulation structure is synthesized using small molecule in situ confinement effects. Meanwhile, the reaction molecular dynamics (RMD) method presents and reveals the mechanism of acetic acid molecules forming a uniform thin carbon layer on the metal surface during heat treatment. The riveted porous carbon shell structure allows rapid electron and mass transfer and acts as a protective layer that limits alloy surface oxidation and maintains the initial catalyst structure. The catalyst exhibits excellent ORR durability, with an initial mass activity (MA) of 94% after 60 000 cycles of accelerated durability tests (ADTs), and is applied to zinc–air batteries and exhibits high current density discharge stability (>100 h, 100 mA cm⁻²).