Engineering Oriented Pt Deposition via Micro–Nano Crisscross Scaffolds: A Paradigm for High‐Efficiency HER Catalyst

A critical issue for the hydrogen evolution reaction (HER) is to break the inherent trade‐off between catalytic activity and mass/charge transport in platinum‐based electrocatalysts. In this work, inspired by the hierarchical coupling of vascular and neural networks in biological systems, we report a high‐performance HER electrocatalyst consisting of platinum nanoparticles anchored on crisscross carbon micro–nanostructures (CCMN). The 3D scaffold simultaneously accelerates charge delivery, proton supply, and hydrogen bubble detachment, thus alleviating key limitations in the electrode process. The Pt/WC/CCMN (2 wt%) catalyst was prepared via controlled carburization of a W‐doped Fe‐BTC precursor, followed by selective Pt deposition through galvanic replacement. Electrochemical measurements reveal that the catalyst delivers 100 mA cm −2 at an overpotential of only 49 mV. H 2 bubbles formed on the Pt/WC/CCMN electrode are relatively large and detach easily from the surface. Notably, Pt/WC/CCMN exhibits a turnover frequency value of 27.16 H 2 s −1 at 100 mV, 3.6 times higher than that of commercial Pt/C (7.41 H 2 s −1 ). This work develops a competitive HER electrocatalyst and also provides a universal design strategy for gas‐involved electrocatalytic reactions.