Ultrathin high-entropy alloy nanowires as a bi-functional catalyst for the hydrogen evolution reaction and methanol oxidation reaction

Abstract

High-entropy alloys (HEAs) have been used as critical electrocatalysts. However, achieving precise atomic-level control over their dimensions and morphologies remains a formidable challenge. In this work, distinctive PtPdRuFeCoNi HEA nanowires (NWs) that possess an average diameter of 1.36 ± 0.05 nm are successfully synthesized. The prepared HEA NWs can serve as a bi-functional electrocatalyst for the hydrogen evolution reaction (HER) and methanol oxidation reaction (MOR) in alkaline solution. The HEA NWs exhibit an ultrasmall overpotential of 14 mV at 10 mA cm⁻² for alkaline HER and long-term durability over 50 h. Furthermore, the HEA NWs exhibit excellent catalytic performance for the MOR with a mass activity of 10.4 A mg_PGM⁻¹, 13.0 times as high as that of commercial Pt/C. This work offers a facile approach for the synthesis of HEA NWs and facilitates the use of highly active HEA-based catalysts in clean energy conversion and utilization.