Bio-Derived Co2 P Nanoparticles Supported on Nitrogen-Doped Carbon as Promising Oxygen Reduction Reaction Electrocatalyst for Anion Exchange Membrane Fuel Cells.

Recently, nonnoble-metal catalysts such as a metal coordinated to nitrogen doped in a carbon matrix have been reported to exhibit superior oxygen reduction reaction (ORR) activity in alkaline media. In this work, Co2 P nanoparticles supported on heteroatom-doped carbon catalysts (NBSCP) are developed with an eco-friendly synthesis method using bean sprouts. NBSCP can be easily synthesized through metal precursor absorption and carbonization at a high temperature. It shows a very large specific surface area with various dopants such as nitrogen, phosphorus, and sulfur derived from small organic molecules. The catalyst can exhibit activity in various electrochemical reactions. In particular, excellent performance is noted for the ORR. Compared to the commercial Pt/C, NBSCP exhibits a lower onset potential, higher current density, and superior durability. This excellent ORR activity and durability is attributable to the synergistic effect between Co2 P nanoparticles and nitrogen-doped carbon. In addition, superior performance is noted on applying NBSCP to a practical anion exchange membrane fuel cell system. Through this work, the possibility of applying an easily obtained bio-derived material to energy conversion and storage systems is demonstrated.

Green synthesis of carbon-supported nanoparticle catalysts by physical vapor deposition on soluble powder substrates.

Metal and metal oxide nanoparticles (NPs) supported on high surface area carbon (NP/Cs) were prepared by the physical vapor deposition of bulk materials on an α-D-glucose (Glu) substrate, followed by the deposition of the NPs on carbon supports. Using Glu as a carrier for the transport of NPs from the bulk materials to the carbon support surfaces, ultrafine NPs were obtained, exhibiting a stabilizing effect through OH moieties on the Glu surfaces. This stabilizing effect was strong enough to stabilize the NPs, but weak enough to not significantly block the metal surfaces. As only the target materials and Glu are required in our procedure, it can be considered environmentally friendly, with the NPs being devoid of hazardous chemicals. Furthermore, the resulting NP/Cs exhibited an improvement in activity for various electrochemical reactions, mainly attributed to their high surface area.