Zijia Li, Tae Hak Kim, Sung Yong Han, Yeo-Jun Yun, Seonghwa Jeong, Bonghyun Jo, Song Ah Ok, Woongbin Yim, Seung Hu Lee, Kangho Kim, Sunghyun Moon, Ji-Yong Park, Tae Kyu Ahn, Hyunjung Shin, Jaejin Lee*, Hui Joon Park*
|Title||Wide-Bandgap Perovskite/Gallium Arsenide Tandem Solar Cells|
|Journal||Advanced Energy Materials|
|Volume and page||10, 201903085 (2020.02.11)
: [Featured as Cover Image of Journal]
: [Featured in various media (연합뉴스, 헤럴드경제, 뉴스1, 베리타스알파, 뉴스윅스, 녹색경제신문, 기계신문 등)]
|Year of publication||2020|
Gallium arsenide (GaAs) photovoltaic (PV) cells have been widely investigated due to their merits such as thin-film feasibility, flexibility, and high efficiency. To further increase their performance, a wider bandgap PV structure such as indium gallium phosphide (InGaP) has been integrated in two-terminal (2T) tandem configuration. However, it increases the overall fabrication cost, complicated tunnel-junction diode connecting subcells are inevitable, and materials are limited by lattice matching. Here, high-efficiency and stable wide-bandgap perovskite PVs having comparable bandgap to InGaP (1.8–1.9 eV) are developed, which can be stable low-cost add-on layers to further enhance the performance of GaAs PVs as tandem configurations by showing an efficiency improvement from 21.68% to 24.27% (2T configuration) and 25.19% (4T configuration). This approach is also feasible for thin-film GaAs PV, essential to reduce its fabrication cost for commercialization, with performance increasing from 21.85% to 24.32% and superior flexibility (1000 times bending) in a tandem configuration. Additionally, potential routes to over 30% stable perovskite/GaAs tandems, comparable to InGaP/GaAs with lower cost, are considered. This work can be an initial step to reach the objective of improving the usability of GaAs PV technology with enhanced performance for applications for which lightness and flexibility are crucial, without a significant additional cost increase.