Amplified Photocurrent in Heterojunctions comprising Nano-rippled Zinc Oxide and Perovskite-inspired Cs3Cu2I5

Si Hyeok Yang; Lim Kyung Oh; Na Young Lee; Dong Ho Lee; Sang Min Choi; Bowon Oh; Yun Ji Park; Yunji Cho; Jaesel Ryu; Hongki Kim; Sang-Hyun Chin; Yeonjin Yi; Myungkwan Song; Han Seul Kim; Jin Woo Choi

arXiv · 2510.23063

Amplified Photocurrent in Heterojunctions comprising Nano-rippled Zinc Oxide and Perovskite-inspired Cs3Cu2I5

Si Hyeok Yang·Lim Kyung Oh·Na Young Lee·Dong Ho Lee·Sang Min Choi·Bowon Oh·Yun Ji Park·Yunji Cho·Jaesel Ryu·Hongki Kim·Sang-Hyun Chin·Yeonjin Yi·Myungkwan Song·Han Seul Kim·Jin Woo Choi

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Abstract

Molecular zero-dimensional (0D) halide perovskite-inspired cesium copper iodide (Cs3Cu2I5) is a highly promising candidate for optoelectronic applications due to their low toxicity, high stability, and intense blue emission. However, their intrinsically poor electrical conductivity, stemming from isolated conductive copper iodide tetrahedra by cesium atoms, severely limits charge transport which poses a critical challenge for optoelectronic applications. In this study, we propose a novel strategy to overcome this limitation by utilizing precisely optimized zinc oxide nanoripple structures within a lateral Cs3Cu2I5 photodetector (PD) architecture featuring interdigitated electrodes (IDEs). The ZnO nanoripple was systematically tuned to improve the percolation paths, providing efficient routes for photogenerated carriers to migrate to the IDEs. Consequently, the optimized heterojunctions comprising Cs3Cu2I5 and ZnO exhibited superior photocurrent compared to the pristine Cs3Cu2I5 counterparts. This nanostructure-mediated charge transport engineering strategy for lateral structured PDs offers a new pathway for utilizing low-conductivity 0D materials for conventional optoelectronics, next-generation Internet of Things sensor networks, and plausibly biosensing applications.

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Si Hyeok Yang, Lim Kyung Oh, Na Young Lee, Dong Ho Lee, Sang Min Choi, Bowon Oh, Yun Ji Park, Yunji Cho, Jaesel Ryu, Hongki Kim, Sang-Hyun Chin, Yeonjin Yi, Myungkwan Song, Han Seul Kim, Jin Woo Choi. 2025-10-27. Amplified Photocurrent in Heterojunctions comprising Nano-rippled Zinc Oxide and Perovskite-inspired Cs3Cu2I5. https://arxiv.org/abs/2510.23063

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