Defect-dominated carbon deposited Pd nanoparticles enhanced catalytic performance of formic acid dehydrogenation

Abstract

The defect-rich characteristic nanostructure carbon favors the changing polarity and electron distribution in carbon matrix, thus facilitating an efficient adsorption of ions. Herein, a B,N,F-tridoped carbon material is successfully prepared on defect-rich sites by directly calcining two sodium salts, namely ethylenediaminetetraacetic acid tetrasodium salt (Na4EDTA) and ammonium tetrafluoroborate (NH4BF4). B refers to electron-donating atoms while F and N are electron-accepting atoms. The co-existence of electron-donating and electron-accepting atoms causes an asymmetrical spin and charge density, favoring palladium nanoparticles (Pd NPs) well dispersed on the carbon matrix. The heteroatoms efficiently control over the growth of Pd NPs and regulate the internal electron density. The catalytic performance is significantly enhanced with the obtained Pd/BNF-C catalyst for formic acid dehydrogenation, which has a lower activation barrier (36.4 kJ/mol) and a better reusability than those of free-heteroatom catalysts. The efficiency might be attributed to the strong interaction between Pd NPs and heteroatoms, and the electrons transfer from carbon material to Pd NPs, with benefits including the significant coupling effect of B,N,F-tridoping down to the atomic scale, abundant surface active defects, in-plane nanopore defects and more adjacent metal active sites.