Department of Mechanical Engineering and Materials Science, University of Pittsburgh , Pittsburgh, Pennsylvania 15261, United States.
ACS Appl Mater Interfaces. 2018 Feb 7;10(5):4697-4704. doi: 10.1021/acsami.7b16499. Epub 2018 Jan 26.
We report highly bendable and efficient perovskite solar cells (PSCs) that use thermally oxidized layer of Ti metal plate as an electron transport layer (ETL). The power conversion efficiency (PCE) of flexible PSCs reaches 14.9% with a short-circuit current density (J) of 17.9 mA/cm, open-circuit voltage (V) of 1.09, and fill factor (ff) of 0.74. Moreover, the Ti metal-based PSCs exhibit a superior fatigue resistance over indium tin oxide/poly(ethylene terephthalate) substrate. Flexible PSCs maintain 100% of their initial PCE even after PSCs are bent 1000 times at a bending radius of 4 mm. This excellent performance of flexible PSCs is due to high crystalline quality and low oxygen vacancy concentration of TiO layer. The concentration of oxygen vacancies in the oxidized Ti metal surface controls the electric function of TiO as ETL of PSCs. A decrease in the oxygen vacancy concentration of the TiO layer is critical to improving the electron collection efficiency of the ETL. Our results suggest that Ti metal-based PSCs possess excellent mechanical properties, which can be applied to the renewable energy source for flexible electronics.
我们报告了一种高度可弯曲且高效的钙钛矿太阳能电池（PSC），其使用热氧化的钛金属板层作为电子传输层（ETL）。柔性 PSC 的功率转换效率（PCE）达到 14.9%，短路电流密度（J）为 17.9 mA/cm，开路电压（V）为 1.09，填充因子（ff）为 0.74。此外，基于 Ti 金属的 PSC 在铟锡氧化物/聚对苯二甲酸乙二醇酯（PET）衬底上表现出优异的抗疲劳性。即使在弯曲半径为 4mm 时弯曲 1000 次后，柔性 PSC 仍能保持初始 PCE 的 100%。柔性 PSC 的这种优异性能归因于 TiO 层的高结晶质量和低氧空位浓度。氧化 Ti 金属表面的氧空位浓度控制着 TiO 作为 PSC 的 ETL 的电功能。降低 TiO 层中的氧空位浓度对于提高 ETL 的电子收集效率至关重要。我们的结果表明，基于 Ti 金属的 PSC 具有优异的机械性能，可应用于柔性电子产品的可再生能源。
