Laser‐Induced Liquid Metal Shaping of Strain‐Rich High‐Entropy Alloy Nanowires for Electrocatalysis and Bioelectrochemical Sensing

ABSTRACT High‐entropy alloy (HEA) nanowires offer unique opportunities for electrocatalysis and bioelectrochemical sensing, yet their synthesis remains fundamentally constrained by kinetic mismatch among constituent elements and the lack of controllable, ultrafast shaping mechanisms. Here, we report a laser‐directed liquid metal nanofabrication (LLMN) strategy that overcomes these limitations by directly manipulating multicomponent alloys in the liquid state. Millisecond‐scale laser irradiation generates transient extreme temperatures that drive complete alloy homogenization and activate a catalytic vapor–liquid–solid growth process, enabling one‐step formation of single‐phase HEA nanowires containing up to nine metallic elements. Crucially, confinement of the molten alloy within in situ–grown carbon nanotubes introduces a previously unexplored shaping mechanism in which reaction‐driven boundary advancement competes with sulfur‐mediated interfacial pinning, imprinting tensile lattice strain and dense stacking faults into the solidified nanowires. As a result, the strain‐engineered HEA nanowires exhibit markedly enhanced oxygen evolution activity compared with nanoparticle analogues, achieving an overpotential of 257 mV at 10 mA cm − 2 with reduced charge‐transfer resistance and accelerated kinetics. Beyond electrocatalysis, Cu‐containing HEA nanowires also enable selective electrochemical creatinine detection with good biocompatibility. Together, this work introduces LLMN as a general, composition‐agnostic route for liquid‐state strain engineering in complex alloys, opening new pathways for designing multifunctional HEA nanostructures.