PdAg Nanoparticles Supported on an Amine-functionalized MOF as a Photo-switchable Catalyst for Hydrogen Storage/Delivery Mediated by CO2/Formic Acid

The effects of depositing Pd alloy nanoparticles (NPs) on an amine-functionalized Fe-metal organic framework (MOF; MIL-88B-NH2) were investigated, with the aim of developing a photo-switchable bifunctional catalyst for hydrogen storage/delivery mediated by CO2/formic acid (FA). The highly dispersed PdAg NPs promoted photocatalytic FA synthesis from CO2 under visible light and inhibited electron-hole recombination by efficiently trapping excited electrons. The release of H2 via the dehydrogenation of FA upon heating was efficiently catalyzed by the electron-rich Pd species generated by alloying with Ag. These Pd species acted as crucial active centers associated with amine-functionalized moieties in the linker groups of the Fe-MOF. A photo-switchable bifunctional catalyst for hydrogen storage/delivery mediated by CO2/formic acid was developed with an amine-functionalized Fe-metal organic framework. The deposition of highly dispersed PdAg nanoparticles inhibited electron-hole recombination in the photocatalytic formic acid synthesis from CO2, while the PdAg nanoparticles acted as crucial active centers in the dehydrogenation of formic acid upon heating.