Fast Synthesis of Nanosized CuGaO ₂ Particles as a p-Type Semiconductor for Photocathodes: Preliminary Investigation in DSSCs

The development of efficient p-type semiconductors is critical for advancing dye-sensitized solar cell (DSSC) technologies, particularly for improving the photocathode performance. Among potential candidates, delafossite-type oxides such as CuGaO 2 have shown promising properties, including wide band gaps, high hole mobility, and favorable dye adsorption characteristics. However, the synthesis of phase-pure, nanoscale CuGaO 2 remains a major challenge, especially through low-temperature routes compatible with device fabrication requirements. This work presents a microwave-assisted hydro-solvothermal method for the controlled synthesis of CuGaO 2 nanoparticles. The influence of three critical parameters (coprecipitation pH, reducing agent quantity, and reaction time) on the phase purity and particle size was systematically investigated. The microwave-assisted approach enables rapid and uniform heating, promoting controlled nucleation and growth, while reducing the overall reaction time. Structural and morphological characterization confirmed the formation of nanoplate CuGaO 2 with high phase purity under optimized conditions, eliminating the need for harsh post-synthesis treatments. This method provides a scalable and efficient route for producing high-quality CuGaO 2 particles, offering a promising platform for integration in next-generation photovoltaic devices, as demonstrated by preliminary p-DSSCs investigations using P1 dye loading.