Low-temperature rapid UV sintering of sputtered TiO for flexible perovskite solar modules

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2024-01, Vol.12 (3), p.1562-1572
• Main Authors: Yoo, Yongseok, Seo, Gabseok, Park, Hee Jeong, Kim, Jichan, Jang, Jihun, Cho, Woosum, Kim, Ji Hwan, Shin, Jooyeon, Choi, Ji Seong, Lee, Donghyeon, Baek, Se-Woong, Lee, Sungkoo, Kang, Seong Min, Kim, Min-cheol, Sung, Yung-Eun, Bae, Seunghwan
• Format: Article
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/d3ta05666j

Perovskite solar cells (PSCs) have attracted considerable attention because of their outstanding photovoltaic performance and low fabrication cost. Conventional TiO 2 ETL preparation methods require high-temperature annealing (>450 °C), which increases the fabrication cost and limits application on flexible substrates. To overcome these drawbacks, we propose a method for fabricating thin TiO 2 films via sputtering at room temperature without thermal annealing. We systematically investigated the effects of the sputtering parameters, ultraviolet (UV) treatment, and thermal sintering on the properties of TiO 2 ETLs for PSCs. With proper UV treatment, the sputtered TiO 2 films exhibited well-matched band alignment, defect reduction, and improvements in the carrier concentration, electron mobility, and hole-blocking ability compared with thermally sintered TiO 2 films. We also fabricated large-area perovskite modules using sputtered and UV-treated TiO 2 films as ETLs on rigid and flexible substrates, and they had maximum power-conversion efficiencies of 18.82% and 14.61%, respectively. This study provides a simple, low-temperature route for fabricating ETLs for flexible perovskite solar modules. Perovskite solar cells (PSCs) have attracted considerable attention because of their outstanding photovoltaic performance and low fabrication cost.