Studies on oxygen evolution reaction performance of porous Co3O4–NiO–B2O3 composites

In this article, Co3O4–NiO–B2O3 composites were synthesized via a simple solution combustion method where B2O3 composition is varied from 0 to 50%. The oxygen evolution performance of the Co3O4–NiO–B2O3 composites was investigated. The 40% of B2O3 added Co3O4–NiO composite exhibits an enhanced OER performance where it requires low overpotential of 322 mV (1.54 V vs. RHE) to reach the current density of 50 mA cm−2, which is much lower than that of the 738 mV (1.96 V vs. RHE) and 492 mV (1.72 V vs. RHE) exhibited by bare screen printed electrode (SPE) and pristine Co3O4–NiO composite, respectively. The enhanced OER performance is attributed to significant enhancement in the accessible surface active sites and decrease in charge transfer resistance. Further, the NCB40 shows excellent OER stability and durability over 25 h of continuous electrolysis.