A new application of nickel-boron amorphous alloy nanoparticles: anode-catalyzed direct borohydride fuel cell

In this work, an amorphous Ni-B alloy was synthesized by chemical reduction and used in a direct borohydride fuel cell (DBFC). Characterization of the catalyst structure, composition, and morphology was performed by XRD, EDX, TEM, and SEM. In addition, the results showed that Ni-B presents as amorphous nanoparticles. The particle diameters ranged from 22 to 25 nm. The cyclic voltammetry (CV) and chronoamperometry (CA) tests proved that Ni-B has better electrocatalytic activity and higher stability towards KBH₄ oxidation compared to a pure Ni catalyst. A single cell was assembled with a Ni-B anode and a LaNi_0.9Ru_0.1O₃ cathode. A peak power density of 180 mW cm⁻² was achieved at room temperature. In addition, the fuel utilization rate was approximately 41% at a constant current density of 200 mA cm⁻², illustrating that some BH₄⁻ hydrolysis occurs on the Ni-B surface. Finally, the cell had no attenuation after 180 h test, showing good stability.