Wang Tao, Lian Gang, Huang Liping, Zhu Fei, Cui Deliang, Wang Qilong, Meng Qingbo, Wong Ching-Ping
State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, P. R. China.
Key Laboratory for Special Functional Aggregated Materials of Education Ministry, School of Chemistry & Chemical Engineering, Shandong University, Jinan 250100, P. R. China.
ACS Appl Mater Interfaces. 2020 Aug 26;12(34):38314-38324. doi: 10.1021/acsami.0c08674. Epub 2020 Aug 14.
Perovskite single-crystal (SC) or quasi-single-crystal (QSC) films are promising candidates for excellent performance of photoelectric devices. However, it is still a great challenge to fabricate large-area continuous SC or QSC films with proper thickness. Herein, we propose a pressure-assisted high-temperature solvent-engineer (PTS) strategy to grow large-area continuous MAPbI QSC films with uniformly thin thickness and orientation. Dramatic grain growth (∼100 μm in the lateral dimension) and adequate boundary fusion are realized in them, vastly eliminating the grain boundaries. Thus, remarkable diminution of the trap density (: 7.43 × 10 cm) determines a long carrier lifetime (τ: 1.7 μs) and superior photoelectric performance of MAPbI-based lateral photodetectors; for instance, an ultrahigh on/off ratio (>2.4 × 10, 2 V), great stability, fast response (283/306 μs), and high detectivity (1.41 × 10) are achieved. The combination properties and performance of the QSC films surpass most of the reported MAPbI. This effective approach in growing perovskite QSC films points out a novel way for perovskite-based optoelectronic devices with superior performance.
钙钛矿单晶（SC）或准单晶（QSC）薄膜是具有优异光电性能的有前途的候选材料。然而，制备具有合适厚度的大面积连续SC或QSC薄膜仍然是一个巨大的挑战。在此，我们提出一种压力辅助高温溶剂工程（PTS）策略，以生长具有均匀薄厚度和取向的大面积连续MAPbI QSC薄膜。在其中实现了显著的晶粒生长（横向尺寸约为100μm）和充分的边界融合，极大地消除了晶界。因此，陷阱密度的显著降低（：7.43×10 cm）决定了基于MAPbI的横向光电探测器的长载流子寿命（τ：1.7μs）和优异的光电性能；例如，实现了超高的开/关比（>2.4×10，2V）、高稳定性、快速响应（283/306μs）和高探测率（1.41×10）。QSC薄膜的综合性能超过了大多数已报道的MAPbI。这种生长钙钛矿QSC薄膜的有效方法为具有优异性能的钙钛矿基光电器件指出了一条新途径。
