The role of Pt doping on electrochemical performance and cost of alkaline water electrolysis catalysts

Abstract

The bottleneck limiting the large-scale application of water electrolysis to produce hydrogen is to improve the electrochemical performance and reduce the cost of catalysts. A series of catalysts (Pt content: 0.005/0.01/0.02/0.03/0.04/0.05/0.08/0.11/0.15 mg cm−2) were prepared by a controllable Pt loading method in this work. Different Pt content not only causes the change of Pt nanoparticle size, but also leads to the adjustment of Ni and Pt charge environment, thus result in different electrochemical properties (resistance, active area, catalytic activity and durability). The catalyst with 0.15 mg cm−2Pt shows the excellent performance (HER: 40 mV@10 mA cm−2, OER: 309 mV@100 mA cm−2, alkaline water electrolysis: 1.74 V@ 400 mA cm−2), exceeding the benchmark Pt/C and RuO2 dropped on nickel mesh. The proper reduction of Pt causes a degradation of electrochemical properties, but it also comes a lower cost and a better durability.