Interfacial electronic structure modulation between Pd and N-containing support for efficient formic acid dehydrogenation

Rational design and fabrication of catalysts with excellent efficiency, high selectivity and outstanding stability is of great significance for the practical application of formic acid dehydrogenation into hydrogen gas. Herein, Pd catalysts with a narrow size distribution around 2.2 nm are deposited on the porous chitosan microspheres, which are produced by the polycondensation with Schiff base linkage. The Pd–N bond configuration is formed upon the abundant amino-group on the chitosan backbone with the surface anchoring Pd nanocluster. The surface charge is redistributed to generate high-valence Pd δ+ species due to the ligand-to-metal charge transfer between Pd and N, thus greatly improving the catalytic performance of formic acid dehydrogenation at room temperature and maintaining outstanding stability during 15 consecutive reaction cycles. The present work paves the way to the rational synthesis of Pd-based catalysts with tunable electronic states for practical purposes.