Dye-Sensitized Solar Cells with Modified TiO₂ Scattering Layer Produced by Hydrothermal Method

Area of Science:

• Materials Science
• Renewable Energy
• Nanotechnology

Background:

• Dye-sensitized solar cells (DSSCs) are a promising photovoltaic technology.
• Efficient light scattering in the photoanode is crucial for enhancing DSSC performance.
• Titanium dioxide (TiO2) is a widely used material for DSSC photoanodes.

Purpose of the Study:

• To synthesize and characterize hydrangea-shaped TiO2 (H-TiO2) aggregates for DSSC applications.
• To investigate the effect of mixing H-TiO2 with commercial P25 TiO2 on DSSC performance.
• To optimize the photoanode structure for improved light scattering and overall conversion efficiency.

Main Methods:

• Hydrothermal synthesis of phase-pure anatase H-TiO2 aggregates.
• Characterization using X-ray diffraction (XRD) to confirm phase purity and morphology.
• Fabrication of DSSC photoanodes with varying ratios of H-TiO2 and P25 TiO2 in a double-layer structure.
• Performance evaluation including open-circuit voltage (Voc), short-circuit current (Jsc), fill factor (FF), and conversion efficiency (η).

Main Results:

• Phase-pure anatase H-TiO2 aggregates (300 nm to 2 μm) were successfully synthesized.
• The optimal mixing ratio of H-TiO2:P25 TiO2 was determined to be 3:7 for the scattering layer.
• The optimized double-layer photoanode (five P25 TiO2 layers + one scattering layer) achieved a conversion efficiency of 8.33%.
• Key performance metrics included Voc of 0.77 V, Jsc of 15.26 mA/cm², and FF of 0.71.

Conclusions:

• Mixing large H-TiO2 particles with smaller P25 TiO2 particles effectively enhances light scattering in DSSC photoanodes.
• The optimized DSSC design demonstrates a significant improvement in energy conversion efficiency.
• This study presents a novel approach for scattering layer engineering in DSSCs.