Highly Porous Pt<sub>2</sub>Ir Alloy Nanocrystals as a Superior Catalyst with High-Efficiency C–C Bond Cleavage for Ethanol Electrooxidation
Fang Yan, Dongjie Cao, Yan Shi, Shiyu Guo, Qi Wang, Genlei Zhang, Peng Cui, Sheng Cheng
Abstract
Achieving high catalytic performance with high CO2 selectivity is critical for commercialization of direct ethanol fuel cells. Here, we report carbon-supported highly porous Pt2Ir alloy nanocrystals (p-Pt2Ir/C) for an ethanol oxidation reaction (EOR) that displays nearly 7.2-fold enhancement in mass activity and promotes antipoisoning ability and durability for the EOR as compared with the commercial Pt/C-JM. Moreover, the catalyst exhibits high CO2 selectivity, 3.4-fold at 0.65 V (vs. SCE) and 4.1-fold at 0.75 V (vs. SCE) higher as compared with the carbon-supported porous Pt nanocrystals (p-Pt/C). The highly porous structure is composed of interconnected one-dimensional (1D) rough branches with an average diameter of only 1.9 nm, largely promoting Pt utilization efficiency and accelerating mass transfer. The 1D rough branch surface exposed many atomic steps/corners endowed with abundant high activity sites. Alloying with Ir can significantly improve the antipoisoning ability, durability, and C–C bond cleavage ability, thereby evidently enhancing its EOR performance.