Roll-to-Roll Flash\nJoule Heating to Stabilize Electrocatalysts\nonto Meter-Scale Ni Foam for Advanced Water Splitting

The seamless integration of electrocatalysts onto the\nelectrode\nis crucial for enhancing water electrolyzers, yet it is especially\nchallenging when scaled up to large manufacturing. Despite thorough\ninvestigation, there are few reports that tackle this integration\nthrough roll-to-roll (R2R) methodology, a technique crucial for fulfilling\nindustrial-scale demands. Here, we develop an R2R flash Joule heating\n(R2R-FJH) system to process catalytic electrodes with superior performance.\nThe electrodes exhibited improved stability and activity, showcasing\nan exceptional performance within an alkaline water electrolysis (AWE)\nsystem. They achieved a low operation potential of 1.66 V at 0.5 A\ncm<sup>–2</sup>, coupled with outstanding durability over the\noperation of 800 h. We further demonstrated a prototype of a rolled-up\nwater splitting apparatus, illustrating the efficiency of R2R-FJH\nelectrodes in producing high-purity hydrogen through advanced water\noxidation. Our study emphasized the practicality and scalability of\nthe R2R-FJH strategy in the industrial manufacturing of high-performance\nelectrodes for water electrolysis.