Investigation of Hydrazine Electrooxidation Performance of Dihydrobenzothienopyranone Derivatives

This work presents the electrochemical activity of five dihydrobenzothienopyranone derivatives, A ₁ -A ₅ , toward the electrooxidation of hydrazine (N₂H₄) in alkaline media (1 M KOH + 0.5 M N₂H₄). All of the prepared catalysts were characterized by cyclic voltammetry (CV), chronoamperometry (CA), electrochemical impedance spectroscopy (EIS), and linear sweep voltammetry (LSV). Dihydrobenzothienopyranone (A ₅ ) exhibits the highest electrochemical activity, with a current density of 38.29 mA/cm². It also exhibited very good long-term stability, showing constant catalytic activities, current density, and low charge transfer resistance during extended periods, with relevant features for efficient energy conversion. These findings thus constitute evidence that A ₅ might be an active but economically feasible alternative to the conventionally used transition metal-based catalysts such as Pd, Au, and Pt at the anodes of direct hydrazine fuel cells. These properties combine high stability and low cost to further make the catalyst an encouraging candidate for fuel cell technologies that are benign to the environment. These results highlight the potential of organic-based materials in fuel cell applications for the future and offer a sustainable alternative to the current metal-based systems.