Semiconductors modified gourd-shaped hollow PtNi and their directional electron and mass transfer effects

Maximization of the utilization of electronic energy and enhancement of mass transfer are important goals in designing high-performance electrocatalytic PtNi nanoalloys. However, realization of such a combination of these properties into Pt based electrocatalysts remains a significant challenge. In an effort targeted at attaining these goals, we prepared several semiconductors (BiVO 4 , CdS and TiO 2 ) modified, gourd-shaped hollow PtNi nanocomposites . We observed that among members of this group, BiVO 4 modified PtNi (denoted as BiVO 4 /PtNi) displays optimal directional electron and mass transfer, which are attributed to the closeness of the work functions of BiVO 4 and PtNi, and a unique gourd-shaped, hollow structure. Moreover, BiVO 4 /PtNi displays remarkable electrocatalytic performance in the hydrogen evolution reaction, in terms of low overpotential of 23 mV to drive the current density of 10 mA cm −2 and a low Tafel slope of 40 mV dec −1 in alkaline natural seawater. Furthermore, this nanocomposite exhibits high stability during a 20-h durability test that greatly exceeds that of commercial Pt/C. The results of this investigation show that new approaches exist for designing novel nanomaterials that have superior performance as electrocatalysts or in other practical applications.