Engineering the high-entropy phase of Pt-Au-Cu nanowire for electrocatalytic hydrogen evolution

Hydrogen economy, as the most promising alternative energy system, relies on the hydrogen production through sustainable water splitting which in turn relies on the high efficiency electrocatalysts. PtAuCu A1-phase alloy has been predicted to be a promising electrocatalyst for the hydrogen evolution. As such preferred phase of Pt-Au-Cu is not thermodynamically favored, herein, we stabilize PtAuCu alloy by engineering the high-entropy phase in the form of nanowire. Density functional theory (DFT) calculations indicate that, in comparison with the ordered phase and segregated phases with discrete hydrogen binding energy, the high-entropy phase provides a diverse combination of site composition to continuously tune the hydrogen binding energy, and thus generate a series of highly active sites for the hydrogen evolution. Reflecting the theoretical prediction, electrochemical tests show that the A1-phase PtAuCu nanowire significantly outperforms its nanoparticle counterpart with phase segregation, toward the electrocatalysis of hydrogen evolution, offering one of the best hydrogen evolution electrocatalysts.