Optimizing the hydrogen evolution reaction by shrinking Pt amount in Pt-Ag/SiNW nanocomposites

摘要

In recent years, platinum-based catalysts are the most promising candidates for hydrogen evolution reaction (HER). Decrease of the Pt usage is an effective way to obtain low-cost hydrogen production. In order to achieve this goal, we synthesized Pt-Ag/SiNW composites with different dosages of Pt, using inexpensive Ag as a co-catalyst and SiNWs as carriers, and tested their catalytic performance in HER. The results showed that the optimal composition of Pt: Ag: Si = 4.1: 21.5: 74.4 in mass ratio. With such a low amount of Pt, the Pt-Ag/SiNW catalyst exhibited exciting HER performance, whose turnover frequency is 6.3H(2)Pt(-1)s(-1) at -0.2 V vs. RHE, 2.7 times as large as that of 40 wt% Pt/C. This design greatly increased the utilization ratio of Pt, which may open a new way for preparation of other Pt-based catalysts. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.