Broadband Flexible Photodetectors Based on CdS x Se 1– x /PbI 2 Heterojunctions

作者：Muhammad Zubair Nawaz, Hafsa Gulzar, Israr Masood ul Hasan, Muhammad Shahrukh Saleem, Asad Khaleeq, Waqar ul Hasan, Muhammad Imran, Mai Li, H. M. Noor ul Huda Khan Asghar, Gul Naz, Anna Baldycheva, Monica F. Craciun, Chunrui Wang, Yu. Yu. Illarionov · 发表于：ACS Applied Electronic Materials · 年份：2024 · DOI：10.1021/acsaelm.4c00476 · 被引用次数：30 · 研究领域：Advanced Semiconductor Detectors and Materials、Quantum Dots Synthesis And Properties、Chalcogenide Semiconductor Thin Films

2D photodetectors can considerably outperform their Si counterparts and thus appear promising for contemporary optoelectronic circuits. However, limited charge separation efficiency and poor optical absorption make it complicated to create ultrasensitive broad response photodetectors using a single 2D material. While hybrid heterostructures combining 2D and 1D materials could be a promising solution, previously used binary/binary 1D/2D photodetectors have a performance that is merely satisfactory at best. To address these limitations, here we for the first time demonstrate vertically stacked ternary/binary photodetectors (VPDs) based on 1D ternary CdS x Se 1– x nanoribbon (NR)/2D binary PbI 2 nanosheets (NS) heterostructures. While excellent crystallinity of the ternary/binary structure enables efficient carrier transport, a type-II heterojunction at the interfaces facilitates charge separation. As a result, our devices exhibit excellent photodetection ability in broad range with superior photoresponsivity (567 A/W), photosensitivity (1.60 × 10 7 %), specific detectivity (1.96 × 10 15 Jones), external quantum efficiency (1.17 × 10 5 %), and the response speed which is several orders of magnitude higher as compared to our reference devices based on PbI 2 NS and most of the previously reported photodetectors in visible range. Furthermore, our VPDs fabricated on flexible substrates show stable operation after being subjected to multiple bending cycles and retain excellent perfor...