Lattice strain controlled Ni@NiCu efficient anode catalysts for direct borohydride fuel cells

We successfully fabricated a novel tensile lattice strained Ni@NiCu catalyst with a popcorn-like morphology, which is composed of a crystalline Ni core and a NiCu alloy shell. It exhibits outstanding catalytic activity, selectivity, and stability towards borohydride electrooxidation. Moreover, a direct borohydride fuel cell (DBFC) with a Ni@NiCu anode can deliver a power density of 433 mW cm(-2) and an open circuit voltage of 1.94 V, much better than the performances of DBFCs employing other anode catalysts reported in the literature. This could be attributed to the fact that the tensile lattice strain generated by the introduction of Cu leads to a rise in the d-band center of the Ni metal and promotes the final B-H decoupling, which is the rate-determining step in the borohydride oxidation reaction, thus improving remarkably the catalytic performances of Ni@NiCu.

Automated summary

Researchers successfully fabricated a novel tensile lattice strained Ni@NiCu catalyst with a popcorn-like morphology, showing excellent catalytic activity, selectivity, and stability in borohydride electrooxidation. Moreover, using a Ni@NiCu anode, a direct borohydride fuel cell (DBFC) achieved a power density of 433 mW cm(-2) and an open circuit voltage of 1.94 V, surpassing the performance of DBFCs with other reported anode catalysts. This improvement can be attributed to the introduction of Cu generating tensile lattice strain, leading to an increase in the d-band center of Ni metal and promoting the rate-determining step of B-H decoupling in borohydride oxidation.