Carbon vacancy defect-activated Pt cluster for hydrogen generation†
Providing specific accommodation for supported metal clusters on the defective sites of supports is vital to disclose the function mechanism of the structural defects on metals and the fabrication of excellent catalysts. Here, stable platinum-group metal clusters (Pt, Pd and Au) trapped by structure defects within carbon nanotubes (CNTs) were fabricated with a simple and scalable in situ electrochemical strategy. The Pt clusters demonstrated superior electrocatalytic activity for the hydrogen evolution reaction (HER) with 100-fold increase over the mass activity of the benchmark 20 wt% Pt/C and a much lower overpotential. It was suggested that vacancy defective structures (di- and mono-vacancies) stabilized the Pt cluster from migration and oxidation and optimized the electronic densities of state, hence activating the Pt species for efficient HER with high stability. These results provide new insights into the effects of structural defects on active phases and afford a facile but competitive strategy to synthesize stable and desired catalysts.