Electrode fabrication of BiFeO3/PANI nanohybrid by solvothermal process for efficient water splitting

Abstract

The rapid depletion of fossil fuels has raised significant concerns in energy sector. The excessive usage of coal and gas for energy production is polluting our environment and ecosystem which is an alarming situation. Therefore, it is essential to explore renewable resources for energy production to overcome this problem. Water splitting is one of the promising sources of renewable energy production. In water electrolysis, catalysts play an important role; in present work, BiFeO₃/PANI is used as an electrocatalyst for OER. BiFeO₃/PANI composite is a remarkable electrocatalyst for water splitting because of its stability and high catalytic activity. BiFeO₃/PANI was fabricated via solvothermal processes, and its structural, morphological, and functional groups were identified by X-ray diffraction, scanning electron microscope (SEM), and Fourier transform infrared spectroscopy. SEM results showed that the BiFeO₃/PANI composite’s surface morphology was flakes that dispersed more evenly across the aggregated nanosheets. The EDS investigation of BiFeO₃/PANI showed that the sample contained C, N, O, Bi, and Fe. To verify the thermal stability, thermogravimetric analysis (TGA) of the BiFeO₃/PANI was carried out at temperatures ranging from 25 to 700 °C. TGA technique confirms the thermal stability of composite. The enhanced surface area and higher conductivity of the composite indicate its efficient OER performance. The synthesized materials were tested for their electrochemical performances in an alkaline medium (KOH), and nanocomposite BiFeO₃/PANI showed exceptional OER capabilities, like less overpotential (278 mV). In addition to facilitating electron transport, the electrocatalyst achieves a low Tafel value (37.83 mV s⁻¹) and exhibits extended durability even after 2500 cycles. These results showed nanocomposite BiFeO₃/PANI is the best electrocatalyst for OER.

Graphical abstract