大连理工大学 化工学院化学系, 精细化工国家重点实验室, 大连 116024
三维(3D)有机-无机金属卤化物钙钛矿薄膜的表面和晶界处存在大量缺陷, 容易导致载流子的非辐射复合并加快3D钙钛矿分解, 进而影响钙钛矿太阳能电池(PSCs)能量转换效率(PCE)及稳定性。本研究通过引入对氯苄胺阳离子, 与3D钙钛矿薄膜及其表面过剩的碘化铅反应后原位形成了二维(2D)钙钛矿, 实现了对3D钙钛矿薄膜表面和晶界处的缺陷钝化并改善了表面疏水性。基于该策略, 成功制备出具有更高PCE和更好稳定性的2D/3D-PSCs。本工作系统研究了钙钛矿薄膜的结构、形貌和器件的光电特性及稳定性。研究结果表明, 2D/3D-PSCs的PCE高达20.88%, 高于3D-PSCs的18.70%。另外, 2D/3D-PSCs连续工作200 h后(1个太阳光, N2氛围), PCE保持初始值的82%, 展现出优异的稳定性。
钙钛矿太阳能电池 缺陷钝化 2D钙钛矿 3D钙钛矿 稳定性 perovskite solar cells defect passivation 2D perovskite 3D perovskite stability
苏州大学, 放射医学及交叉学科研究院, 放射医学与辐射防护国家重点实验室, 苏州 215123
钙钛矿材料在太阳能电池和光电探测等领域的快速发展, 带动了其在核辐射探测领域的应用研究。钙钛矿晶体结构拥有多样化的结构容忍性, 如何设计组分并挖掘材料的相关特性具有很大的科学挑战。其次, 针对新型钙钛矿材料特性, 需要根据应用场景来优化半导体器件设计, 才能最大限度地发挥其辐射探测性能。鉴于此, 本文从熔体法晶体生长及半导体器件设计等角度, 探讨了不同维度钙钛矿结构的材料特性及辐射探测器件性能, 以期为该材料在核辐射探测领域的发展提供参考。
无机钙钛矿半导体 熔体法 单晶 半导体器件 核辐射探测 三维钙钛矿 二维钙钛矿 缺陷钙钛矿 inorganic perovskite semiconductor melt-grown method single crystal semiconductor device nuclear radiation detection 3D perovskite 2D perovskite defect perovskite
Author Affiliations
Abstract
School of Optical and Electronic Information and Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China
Two-dimensional (2D) perovskites exhibit broadband emission due to strong exciton–phonon coupling-induced self-trapped excitons and thus would find important applications in the field of white-light emitting devices. However, the available identifying methods for self-trapped excitons are currently rather limited and complex. Here, we identify the existence of self-trapped excitons by Raman spectroscopy in both excited and non-excited states. Under excited states, the shifting of the Raman peak indicates the presence of the lattice distortion, which together with the extra Raman scattering peak reveals the presence of self-trapped excitons. Our work provides an alternative simple method to study self-trapped excitons in 2D perovskites.
self-trapped excitons 2D perovskite Raman spectrum excited states Chinese Optics Letters
2021, 19(10): 103001
