A CoMo@NiC2O4/NF anode and a Pb/CP cathode for a novel direct sodium borohydride-maleic acid fuel cell

Abstract

In this paper, a CoMo@NiC₂O₄/NF electrode with a spherical nanoflower-like structure and a Pb/CP electrode with Pb nanoflowers are prepared, which are used as the anode and cathode, respectively, to assemble a novel direct sodium borohydride-maleic acid fuel cell (DBMAFC). When the solution contained 1.0 mol dm⁻³ NaOH and 0.5 mol dm⁻³ NaBH₄, the CoMo@NiC₂O₄/NF electrode catalyzed the electrooxidation of NaBH₄ up to a high current density of 490 mA cm⁻² (−0.3 V). The electrode has a high electrochemically active surface area of 299 cm², which facilitates contact between the active substance and the reaction solution to significantly improve electrochemical performance. The number of transferred electrons is 7.5, which is close to the theoretical number of transferred electrons (8e⁻). The Pb/CP electrode generates a high reduction current density of 232 mA cm⁻² (−1.0 V) in a mixed solution of 1.0 mol dm⁻³ H₂SO₄ and 0.2 mol dm⁻³ C₄H₄O₄. The DBMAFC shows good stability with the highest power density of 25 mW cm⁻². While the fuel cell generates electricity, the C₄H₆O₄ produced from the cathode area is an important chemical product with a purity of 97%. This work demonstrates the superiority of CoMo@NiC₂O₄/NF and Pb/CP electrodes in the DBMAFC with high application potential.