Synthesis and Characterization of Undoped and Strontium-Doped Zinc Ferrites for Applications of Solid Oxide Fuel Cells and Photocatalytic Hydrogen Generation

This study aims to synthesize and characterize the undoped and strontium-doped spinel zinc ferrites for the application of cathode material in solid oxide fuel cells (SOFC) and photocatalytic hydrogen generation through sodium borohydride (NaBH₄) methanolysis. Composite strontium iron zinc-based SOFC cathode materials are fabricated by the Sol–Gel technique. XRD patterns collected from powders that were prepared by calcining the gels at 800°C confirmed the presence of pure franklinite (ferrites) material for the undoped material. Scanning electron microscopic images depicted compact and distinct particles with broad size ranges and irregular boundaries. Tauc plots of the synthesized materials depicted the bandgaps in the range of 2 to 1.45 eV, which confirms the potential of the synthesized materials to harvest light in the visible range. By incorporating the strontium content, strontium zinc ferrite, a new material appeared along with the pure franklinite phase. Conductivity was found to be enhanced with increasing strontium content. The photocatalytic behavior of the synthesized magnesium ferrites for hydrogen generation by NaBH₄ methanolysis was evaluated by water displacement reaction. The results confirmed the potential of the synthesized material for hydrogen generation in the presence of UV irradiation.