多功能添加剂对全无机钙钛矿光电器件性能影响的研究

Study on Effect of Multifunctional Additives on Performance of All-inorganic Perovskite Photovoltaic Devices

钙钛矿吸光层CsPbI3-xBrx中的离子迁移、较多的表面缺陷以及较差的薄膜质量限制了钙钛矿光电器件能量转换效率的提高。因此,将多功能添加剂硫氰酸胍(GuSCN)加入钙钛矿前驱体溶液中,利用Gu^(+)和[PbI_(6)]^(4-)之间的强氢键抑制钙钛矿中的离子迁移。同时GuSCN中的SCN^(-)不仅可以作为伪卤素减少钙钛矿中的卤素缺陷数量,还能诱导奥斯瓦尔德熟化增加晶粒尺寸获得高质量薄膜。最终获得了具有优良稳定性、良好结晶性的高质量钙钛矿吸光层薄膜。将处理后的薄膜制备成全无机钙钛矿光电器件,发现能量转换效率由原始的9.01%提高到11.73%,进一步证明多功能添加剂能有效提高光电器件的性能。

Ion migration in the light-absorbing layer of CsPbI_(3-x)Br_(x),more surface defects and poor film quality limit the improvement of power conversion efficiency(PCE)of perovskite optoelectronic devices.Therefore,the multifunctional additive guanidinium thiocyanate(GuSCN)was added into the solution of the perovskite precursor to inhibit ion migration by utilizing the strong hydrogen bond between Gu+and[PbI6]^(4-).Meanwhile,SCN^(-)in GuSCN not only acted as a pseudohalide to reduce the number of halide defects in the perovskite,but also induced Oswald ripening to increase the grain size to obtain high-quality films.Finally,high-quality light-absorbing layer films with excellent stability and good crystallinity was obtained.The treated films were used into all-inorganic perovskite optoelectronic devices,it was found that the PCE increased from the original 9.01%to 11.73%,further demonstrating that the multifunctional additives could effectively improve the performance of optoelectronic devices.