Facile MOF Support Improvement in Synergy with Light Acceleration for Efficient Nanoalloy-Catalyzed H₂ Production from Formic Acid

Hydrogen (H₂) generation and storage are actively investigated to provide a green source of energy, and formic acid (HCOOH), a major product obtained from the biomass, is regarded as a productive source of H₂. Therefore, improvements in heterogeneous catalysts are called for. Here, a novel type of catalyst support is proposed involving simple addition of the mixture of metal ion precursors to core-shell ZIF-8@ZIF-67, followed by reduction with NaBH₄, with performances surpassing those obtained using nanocatalysts in ZIF-8 or ZIF-67. The nanocatalysts PdAg were optimized with ZIF-8@Pd₂Ag₁@ZIF-67 under visible-light illumination for selective HCOOH dehydrogenation involving a turnover frequency value of 430 h^-1 under light irradiation at 353 K. These results also reveal the crucial roles of the Pd sites electronically promoted in the presence of visible light by the Ag plasmon resonance and the advantageous core-shell MOF structure. In order to examine the potential of extending this catalyst improvement principle to other catalytic reactions, 4-nitrophenol reduction, a benchmarking model of catalytic reaction, was tested, and the results also confirmed the superiority of the performance of ZIF-8@Pd₂Ag₁@ZIF-67 over Pd₂Ag₁@ZIF-8 and Pd₂Ag₁@ZIF-67, confirming the interest in the novel catalyst design.