Presentation Information
[3P99]Evaluation of photoexcited carrier dynamics at the interface of perovskite solar cells using terahertz emission spectroscopy
*Tatsu Murao1, Adarsh Parajapati2, Toshimitsu Mochizuki3, Katsuto Tanahashi3, Razanoelina Manjakavahoaka1, Hidetoshi Nakanishi1, Toshiya Doi1, Iwao Kawayama1 (1. Graduate School of Energy Science, Kyoto University, 2. Department of Mechanical Engineering, Indian Institute of Technology Bombay, 3. National Institute of Advanced Industrial and Science Technology)
Perovskite solar cells (PSCs), which utilize perovskite-structured material as the active layer, have demonstrated remarkable power conversion efficiency. A solar cell must have a built-in electric field suitable for separating and extracting photo-generated electrons and holes in the active layer for their highly efficient operation. However, the band structures at the interface and carrier dynamics in PSCs remain insufficiently understood. Recently, we evaluated the surface state of PSCs using terahertz (THz) emission spectroscopy (TES) that measured the waveforms of THz emissions from samples excited by femtosecond laser pulses. Samples were prepared with and without an IPA solution as a passivating agent at the perovskite layer interface. THz waves were observed from both samples and the passivated sample exhibited faster relaxation of THz waves compared to the non-passivated sample, indicating that passivation may accelerate current relaxation. Our results suggest that TES provides valuable insights into the role of interface passivation in enhancing carrier dynamics and overall efficiency of PSCs.