Electrodeposition of Poly(3,4-ethylenedioxythiophene) @Ni(OH)2 hybrid material on carbon microfibres for ammonia oxidation in alkaline media

Ammonia oxidation reaction (AOR) is an intriguing field of research with significant potential to address global energy challenges and advance a greener, more sustainable future by harnessing its role as a renewable energy source. In this study, we present a hybrid platform composed of carbon microfibres that have been modified with poly(3,4-ethylenedioxythiophene) and nickel hydroxide/oxyhydroxide (CP/PEDOT@Ni(OH)(2). Morphological and spectroscopic analyses (SEM-EDS, XPS, and FTIR-ATR) confirmed that the PEDOT film uniformly surrounds the carbon microfibre, creating a surface platform suitable for electrodepositing Ni species. The electrochemical parameters that were ascertained included the surface coverage of Ni active species (Gamma(0)* = 1.77 nmol<middle dot>cm(-2)), the electrochemically active surface area (EASA = 113.3 cm(2)), the electron transfer coefficient (alpha = 0.32), and the heterogeneous electron transfer rate constant (k(s) = 16.68 s(-1)). Electrochemical evaluation for AOR revealed that CP/PEDOT@Ni(OH)(2) exhibits a Tafel slope of similar to 30 mV<middle dot>dec(-1), confirming enhanced charge transfer properties. Electrochemical impedance spectroscopy (EIS) revealed a decline in capacitance and charge-transfer resistance in the presence of ammonia, suggesting the presence of active sites for charge storage and transfer, which are controlled by the diffusion process at the PEDOT@Ni(OH)(2)/solution interface. These findings underscore the synergistic contribution of PEDOT and Ni oxyhydroxide in facilitating electron and ion transport, thereby establishing CP/PEDOT@Ni(OH)(2) as a promising anode electrocatalyst for low-temperature direct ammonia fuel cells.