Construction of chiral-2D/3D perovskite heterojunction films for efficient circularly polarized light detection

• Published in: Journal of materials chemistry. C, Materials for optical and electronic devices Vol. 11; no. 36; pp. 12392 - 12399
• Main Authors: Tao, Liting, Tang, Wei, Yan, Minxing, Ding, Li, Wei, Jiajun, Wang, Lixiang, Li, Liqi, Li, Linjun, Yang, Deren, Fang, Yanjun
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 21.09.2023
• Subjects: Anisotropy; Carrier transport; Charge transport; Circular polarization; Current carriers; Energy transfer; Excitons; Heterojunctions; Insulation; Ligands; Perovskites; Polarized light; Spin coating; Spintronics; Thin films
• ISSN: 2050-7526; 2050-7534
• DOI: 10.1039/d3tc01534c

2D Ruddlesden-Popper perovskites with chiral organic ligands are emerging as promising candidates for circularly polarized light (CPL) detection, which has important applications in quantum communication and opto-spintronics. However, the insulating organic spacers in 2D perovskites generally hinder carrier transport and charge extraction, hence leading to a low responsivity of photodetectors. Herein, we have prepared a chiral-2D/3D perovskite heterojunction thin film via intermittent spin-coating of the chiral-2D ligands on top of a 3D perovskite film. The chiral-2D perovskite formed on top of the film functions as the CPL absorption layer, while the energy transfer between chiral-2D and 3D perovskites and the dissociation of excitons in the 3D phase facilitate the efficient lateral carrier transport and extraction in the bottom 3D perovskite-based charge transport channel. The resultant heterojunction CPL detectors exhibit a high anisotropy factor of 0.13 and a large specific detectivity of above 6.8 × 10 10 Jones that significantly outperform those of the pure chiral-2D based ones, which paves the way for the design and preparation of high performance perovskite thin film-based CPL detectors. A chiral-2D/3D perovskite heterojunction is prepared via intermittent spin-coating of the chiral-2D ligands on top of a 3D perovskite film, which shows enhanced circularly polarized light detection performance as compared to the chiral-2D based ones.