Nguyen Bich Phuong, Youn Sarah Su-O, Kim Yeon Soo, Nguyen Thuy Thi, Park Ha Kyung, Kim Gee Yeong, Jo William
New and Renewable Energy Research Center (NREC), Ewha Womans University, Seoul 03760, Republic of Korea.
Department of Physics, Ewha Womans University, Seoul 03760, Republic of Korea.
Nanoscale. 2025 Jun 26;17(25):15239-15251. doi: 10.1039/d5nr00992h.
Manipulating charge carrier recombination dynamics in mixed three-dimensional (3D) and two-dimensional (2D) perovskites is an effective approach to enhance performance and long-term stability in both solar cells and light-emitting diodes (LEDs). Due to high crystallinity and a low charge carrier recombination coefficient, photogenerated charge carriers in solar cells can effectively diffuse across the perovskite layer, while enhancing radiative recombination through charge carrier confinement can significantly improve electroluminescence efficiencies in LEDs. Further improvements in device efficiency and stability require a comprehensive understanding of charge carrier transport at the numerous interfaces between the different phases of 2D perovskites at both the micro- and nanoscale, as well as ion migration. In this study, we examine the carrier transport mechanism at the thin-surface 2D/bulk 3D perovskite interface and the dense-surface 2D/3D heterophase. The electrical properties and ion migration behavior were analyzed by examining the transition of the - characteristics in both vertical and lateral devices. We carefully analyzed the influence of nanostructures on charge transport using conductive atomic force microscopy (C-AFM) and Kelvin probe force microscopy (KPFM). The variation in the spatial response of the photocurrent and surface photovoltage across grains and grain boundaries with different phases of the 2D perovskite was carefully examined. These insights provide a pathway for optimizing the electrical properties and charge transport behavior of mixed perovskites, further positioning them as key materials for the development of efficient and stable optoelectronic devices.
调控混合三维（3D）和二维（2D）钙钛矿中的电荷载流子复合动力学是提高太阳能电池和发光二极管（LED）性能及长期稳定性的有效方法。由于具有高结晶度和低电荷载流子复合系数，太阳能电池中的光生电荷载流子能够有效地扩散穿过钙钛矿层，而通过电荷载流子限制增强辐射复合可显著提高LED的电致发光效率。要进一步提高器件效率和稳定性，需要全面了解二维钙钛矿不同相之间在微米和纳米尺度上众多界面处的电荷载流子传输以及离子迁移情况。在本研究中，我们研究了薄表面二维/体相三维钙钛矿界面和致密表面二维/三维异相中的载流子传输机制。通过研究垂直和横向器件中-特性的转变来分析电学性质和离子迁移行为。我们使用导电原子力显微镜（C-AFM）和开尔文探针力显微镜（KPFM）仔细分析了纳米结构对电荷传输的影响。仔细研究了二维钙钛矿不同相的晶粒和晶界上光电流和表面光电压的空间响应变化。这些见解为优化混合钙钛矿的电学性质和电荷传输行为提供了一条途径，进一步将它们定位为开发高效稳定光电器件的关键材料。
