Synergistic Effects in Ultrafine Molybdenum–Tungsten Bimetallic Carbide Hollow Carbon Architecture Boost Hydrogen Evolution Catalysis and Lithium‐Ion Storage

Abstract Constructing hierarchical heterostructures is considered a useful strategy to regulate surface electronic structure and improve the electrochemical kinetics. Herein, the authors develop a hollow architecture composed of MoC 1‐ x and WC 1‐ x carbide nanoparticles and carbon matrix for boosting electrocatalytic hydrogen evolution and lithium ions storage. The hybridization of ultrafine nanoparticles confined in the N‐doped carbon nanosheets provides an appropriate hydrogen adsorption free energy and abundant boundary interfaces for lithium intercalation, leading to the synergistically enhanced composite conductivity. As a proof of concept, the as‐prepared catalyst exhibits outstanding and durable electrocatalytic performance with a low overpotential of 103 and 163 mV at 10 mA cm −2 , as well as a Tafel slope of 58 and 90 mV dec −1 in alkaline electrolyte and acid electrolyte, respectively. Moreover, evaluated as an anode for a lithium‐ion battery, the as‐resulted sample delivers a rate capability of 1032.1 mA h g −1 at 0.1 A g −1 . This electrode indicates superior cyclability with a capability of 679.1 mA h g −1 at 5 A g −1 after 4000 cycles. The present work provides a strategy to design effective and stable bimetallic carbide composites as superior electrocatalysts and electrode materials.