Co₃O₄-FeOOH as a heterojunction electrocatalyst for highly-efficient hydrazine-assisted water electrolysis and pollutant degradation

The hydrazine oxidation reaction (HzOR) offers a promising alternative to mitigate the high energy demands associated with the kinetically sluggish oxygen evolution reaction. Consequently, developing an efficient electrocatalyst for HzOR is crucial. In this study, we present a highly effective Co₃O₄-FeOOH heterojunction designed to enhance hydrazine-assisted water splitting performance. Various characterization techniques were employed to analyze the structures and compositions of the catalyst. Evaluations of its electrocatalytic performance revealed exceptional catalytic activity during hydrazine electrolysis, achieving a current density of 100 mA cm⁻² with a minimal negative potential of −17.2 mV (vs. RHE). The system exhibited impressive stability, maintaining consistent performance for over 100 h during HzOR. Notably, the heterostructure electrocatalyst demonstrated outstanding performance and stability in simulated seawater, requiring only −70 mV (vs.RHE) to deliver a current density of 100 mA cm⁻² and remaining stable after the durability test. The electrocatalyst also performed well in harsh environments, including brine and highly alkaline environments. These findings highlight the potential of the Co₃O₄-FeOOH heterostructure electrocatalyst for energy-efficient hydrogen production and pollutant degradation.