温度诱导的梯度锡-铅基混合卤素钙钛矿光电探测器

Temperature-induced gradient tin–lead-mixed halide perovskite photodetector

无机锡(Sn)–铅(Pb)基混合卤素钙钛矿由于其宽的响应波长范围和高的热稳定性,比有机–无机复合铅基卤素钙钛矿更具有吸引力.为了进一步提高Sn–Pb基混合卤素钙钛矿器件的性能,有必要进一步操纵载流子分离和复合.本文提出了一种基于梯度无机CsPb_(0.7)Sn_(0.3)I3的自驱动光电探测器.通过调节退火温度优化CsPb_(0.7)Sn_(0.3)I3基钙钛矿膜中Sn和Pb梯度分布的程度,最终,最优的梯度钙钛矿器件表现出高的响应度(0.18 A W^(−1)),大的比探测率(2.5×10^(12)Jones),和快的响应速率(58.9/42μs),与之前报道的大多数Sn–Pb混合或纯Sn钙钛矿光电探测器性能相当.器件性能的提高主要归因于梯度分布诱导的能带弯曲促进了光生载流子的分离和传输.

Inorganic tin(Sn)–lead(Pb)-mixed halide perovskites have attracted more interest than organic–inorganic hybrid lead halide perovskites due to their broad response wavelength range and high thermal stability.To improve the performance of Sn–Pb-mixed halide perovskite-based devices,it is essential to further manipulate carrier separation and recombination.Herein,a gradient inorganic CsPb_(0.7)Sn_(0.3)I3-based self-powered photodetector is presented.By adjusting the annealing temperature to optimize the gradient distribution degree of Sn and Pb in CsPb_(0.7)Sn_(0.3)I3 perovskite films,the optimal gradient perovskite device exhibits a high responsivity(0.18 A W^(−1)),large specific detectivity(2.5×10^(12)Jones),and fast response speed(58.9/42μs).The performance is comparable to the majority of Sn–Pb-mixed or pure Sn perovskitebased photodetectors reported previously.Correspondingly,the improved performance could be mainly attributed to the gradient distribution-induced band bending,which promotes the separation and transport of photogenerated carriers.