Zinc Stannate (Zn₂SnO₄)-Based Hybrid Composite Photoanode for Dye-Sensitized Solar Cell Application

Improving the power conversation efficiency of dye-sensitized solar cells (DSSCs) has become a challenge and a matter of interest for researchers. Designing a simple device structure with better performance by a cost-effective fabrication technique is essential for photovoltaic technology. This study emphasizes an alternative hybrid composite photoanode material for the DSSC devices. Pristine Zn2SnO4 and Zn2SnO4-SnO2 and Zn2SnO4-ZnO composites were synthesized by facile solid-state calcination to prepare the photoanode for DSSCs. The structural, surface morphological, optical, and band structural properties of the synthesized samples were studied. An attempt has been made to correlate the power conversion efficiency of the fabricated devices with the investigated properties. The X-ray diffraction analysis confirms the presence of multiphases that depend on the stoichiometric ratio of precursor materials. The surface morphology analysis reveals that the Zn2SnO4-SnO2 and Zn2SnO4-ZnO composites exhibit microsheet and microrod structures, respectively. The composite materials show a higher amount of dye loading, leading to better performance than the pristine Zn2SnO4 sample. A better band matching of the synthesized composite materials with other layers provides a higher carrier density. The composite photoanodes exhibit higher efficiency (6.26% for Zn2SnO4-SnO2 and 4.48% for Zn2SnO4-ZnO) than the pristine Zn2SnO4 photoanode (3.76%). The results indicate that the Zn2SnO4-based composites can be potential materials for photoanode applications.