Mesoporous N-Doped Carbon-Confined PdNi Nanoclusters for Efficient and Robust Dehydrogenation of Additive-Free Formic...

Formic acid is a promising liquid organic hydrogen carrier, thanks to its high volumetric hydrogen storage density, easy storage and transport, and potential for regeneration from CO₂. However, developing efficient, durable, and cost-effective catalysts for additive-free formic acid dehydrogenation (FAD) remains a considerable challenge. Herein, ultrafine PdNi nanoclusters (~1.5 nm) were successfully confined within amine-functionalized mesoporous N-doped carbon (AMNC) through a facile impregnation-reduction strategy. The resultant PdNi/AMNC exhibits exceptional catalytic performance for additive-free FAD, achieving complete FA conversion and 100% H₂ selectivity across a temperature range from 303 to 333 K. At 323 K, the catalyst demonstrates a high initial turnover frequency of 5751 h^-1. Remarkably, it maintains quantitative conversion and perfect H₂ selectivity over 20 consecutive reaction cycles, highlighting its superior stability compared to most reported systems. The high catalytic activity primarily stems from the formation of electron-enriched PdNi nanoclusters, driven by the strong electronic metal-support interaction between PdNi and AMNC, as well as electronic coupling between Pd and Ni. Isotope experiments confirmed that the dissociation of CH bond in FA is more difficult than that of OH bond on PdNi/AMNC catalyst in FAD. This work offers a practical design strategy for constructing high-performance bimetallic nanocatalysts for sustainable hydrogen production.