Efficient Perovskite Solar Cells Depending on TiO2 Nanorod Arrays

Area of Science:

• Materials Science
• Renewable Energy
• Nanotechnology

Background:

• Perovskite solar cells (PSCs) are promising for high photovoltaic performance.
• Titanium dioxide (TiO2) nanorod arrays are utilized in PSCs, but efficiencies have been underestimated.
• Optimizing TiO2 nanorod morphology is crucial for enhancing PSC performance.

Purpose of the Study:

• To develop a method for fabricating highly efficient PSCs using tailored TiO2 nanorod arrays.
• To investigate the impact of nanorod length and morphology on PSC performance.
• To achieve a record power conversion efficiency for TiO2 nanorod-based PSCs.

Main Methods:

• A solvothermal method using a modified ketone-HCl system with organic acids was employed to modulate TiO2 nanorod array films.
• TiO2 nanorod arrays with lengths up to approximately 200 nm were fabricated.
• UV-ozone treatment was used to eliminate organic residues on nanorod surfaces.

Main Results:

• Efficient nanorod-structured PSCs were achieved with optimized TiO2 nanorod lengths.
• A record power conversion efficiency of 18.22% was obtained under reverse scan conditions.
• Key optimization strategies included preventing direct contact between TiO2 and hole transport materials and tuning nanorod morphology.

Conclusions:

• The developed solvothermal method enables the fabrication of highly efficient PSCs with TiO2 nanorod arrays.
• Optimizing TiO2 nanorod morphology and surface properties is critical for maximizing PSC performance.
• This work demonstrates the potential of TiO2 nanorod arrays for achieving state-of-the-art PSC efficiencies.