Ternary nickel–tungsten–copper alloy rivals platinum for catalyzing alkaline hydrogen oxidation
Shuai Qin, Yu Duan, Xiaolong Zhang, Lirong Zheng, Fei‐Yue Gao, Peng‐Peng Yang, Zhuang‐Zhuang Niu, Ren Liu, Yang Yu, Xusheng Zheng, Junfa Zhu, Min‐Rui Gao
Abstract
Abstract Operating fuel cells in alkaline environments permits the use of platinum-group-metal-free (PGM-free) catalysts and inexpensive bipolar plates, leading to significant cost reduction. Of the PGM-free catalysts explored, however, only a few nickel-based materials are active for catalyzing the hydrogen oxidation reaction (HOR) in alkali; moreover, these catalysts deactivate rapidly at high anode potentials owing to nickel hydroxide formation. Here we describe that a nickel–tungsten–copper (Ni 5.2 WCu 2.2 ) ternary alloy showing HOR activity rivals Pt/C benchmark in alkaline electrolyte. Importantly, we achieved a high anode potential up to 0.3 V versus reversible hydrogen electrode on this catalyst with good operational stability over 20 h. The catalyst also displays excellent CO-tolerant ability that Pt/C catalyst lacks. Experimental and theoretical studies uncover that nickel, tungsten, and copper play in synergy to create a favorable alloying surface for optimized hydrogen and hydroxyl bindings, as well as for the improved oxidation resistance, which result in the HOR enhancement.