Ultrafast Joule heating method for synthesizing CoNi nanoalloy catalysts for electrocatalytic hydrogen evolution

The hydrogen evolution reaction (HER) is a critical electrochemical reaction in water splitting. However, existing noble metal catalysts tend to aggregate and dissolve under acidic conditions, resulting in low preparation efficiency, poor catalytic activity, and stability. To address this issue, this study employed an ultrafast Joule heating (UJH) technique to rapidly synthesize a cobalt-nickel nanoalloy heterostructure supported on carbon cloth (Co-Ni@CC) and tested its performance in electrocatalytic HER under acidic conditions. The study demonstrated that the metallic heterostructure of Co and Ni nanocrystals on a conductive carbon cloth substrate exhibited excellent dispersion, significantly increasing the contact area of active sites and delivering superior electrocatalytic performance ( η 10 = 231 mV, 111.7 mV dec −1 ). With its high catalytic activity, low cost, good electrical conductivity, and chemical stability, Co-Ni@ CC represents an ideal alternative to noble metal catalysts. Furthermore, this study demonstrates the potential of the UJH technique for rapidly constructing high-performance metal heterostructures, offering a new approach for developing electrocatalysts for overall water splitting.