Jiaqi Wang, Xiang Guan, Xiuling Li, Jinli Liu, Chunli Zhao, Junnan Wang, Yourong Wu, Chengjie Wang, Zhuojian Li, Renjing Chen, Peng Wu, Xueting Liu, Zixun Zhao, Zemin Wang, Yingjie Zhao, Zongwen Liu, Jiao Liu, Xin Tong, Zhiming Wang, Zhanhua Wei, Kebin Lin
Near-infrared spin-light-emitting diodes (NIR-Spin-LEDs), which generate circularly polarized light, offer opportunities for applications such as biomedicine. However, the longest reported emission wavelength of NIR-Spin-LEDs remains limited to 782 nm, making spin-polarized electroluminescence beyond 800 nm challenging. Here we show NIR-Spin-LEDs based on a mixed-dimensional tin-based perovskite heterostructure incorporating chiral R/S-α-methylbenzylammonium (R/S-MBA+) spacer cations. The low-dimensional phases induced by R/S-MBA+ provide chiroptical activity, while three-dimensional FA0.9Cs0.1SnI3 domains serve as the near-infrared emissive centers. Controlled crystallization produces a cypress-leaf-like morphology that promotes carrier confinement and improves charge-injection balance. The resulting devices exhibit electroluminescence peaking at 905 nm, with an external quantum efficiency of 7.8% and a maximum electroluminescence dissymmetry factor (gEL) of 5.5 × 10-2. This work extends spin-polarized electroluminescence into the deep near-infrared region and provides a strategy for developing lead-free NIR-Spin-LEDs.