Low-Temperature Processed TiO_x Electron Transport Layer for Efficient Planar Perovskite Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• High-efficiency perovskite solar cells (PSCs) commonly utilize titanium dioxide (TiO₂) as an electron transport layer (ETL).
• Traditional TiO₂ ETL fabrication requires high-temperature sintering (>450 °C), limiting applications in low-cost and flexible solar devices.

Purpose of the Study:

• To develop a facile, low-temperature chemical bath deposition method for fabricating dense, uniform, and pinhole-free titanium oxide (TiO_x) films.
• To evaluate the performance of low-temperature processed TiO_x as an ETL in planar perovskite solar cells (PSCs).
• To compare the photovoltaic properties of PSCs using low-temperature treated TiO_x with those using high-temperature treated TiO₂.

Main Methods:

• Chemical bath deposition was employed to prepare compact titanium oxide (TiO_x) films at a low temperature of 80 °C.
• Planar perovskite solar cells (PSCs) were fabricated using the low-temperature processed TiO_x as the electron transport layer (ETL).
• Photovoltaic performance was characterized and compared between devices with low-temperature treated TiO_x (<150 °C) and high-temperature treated TiO₂ (>450 °C).

Main Results:

• A dense, uniform, and pinhole-free TiO_x film was successfully fabricated via a low-temperature chemical bath deposition process.
• Perovskite solar cells (PSCs) employing high-temperature treated TiO₂ achieved a power conversion efficiency (PCE) of 15.50%.
• PSCs utilizing the low-temperature treated TiO_x ETL demonstrated a comparable PCE of 14.51%.

Conclusions:

• Low-temperature processed titanium oxide (TiO_x) is a viable and high-quality electron transport layer (ETL) for efficient planar perovskite solar cells (PSCs).
• The findings suggest that low-temperature processed TiO_x can serve as a potential ETL candidate, offering a pathway for developing cost-effective and flexible solar modules.