Embedding Te 4+ into Sn 4+ -Based Metal Halide To Passivate Structure Defects for High-Performance Light-Emitting Application.
Lei ZhouShuigen ZhouXiaowei LiuJunhao MaTing ZhangKailei LiYuanyuan ChangWei ShenMing LiRong-Xing HePublished in: Inorganic chemistry (2024)
Low-dimensional lead-halide hybrids are an emerging class of optical functional material but suffer the problems of toxicity and poor air stability. Among lead-free metal halides, tin(IV)-based metal halides are promising optoelectronic materials due to their robust structure and environmental friendliness. However, their photoluminescence (PL) properties are poor, and the underlying mechanisms are still elusive. Herein, a stable Sn 4+ -based halide hybrid, (C 4 H 7 N 2 ) 2 SnCl 6 , was developed, which however exhibits poor PL properties at room temperature (RT) due to the lattice defects and the robust crystal structure. To enhance its PL efficiency, the Te 4+ ion with a stereoactive 5s 2 lone pair has been introduced into the lattice. As a result, Te 4+ -doped (C 4 H 7 N 2 ) 2 SnCl 6 displays broadband orange emission (∼640 nm) with a PL efficiency of ∼46% at RT. Interestingly, Te 4+ -doped (C 4 H 7 N 2 ) 2 SnCl 6 shows triple emission bands at 80 K, which could be due to the synergistic effect of the organic cations and the self-trapped state induced by Te 4+ . Additionally, high-performance white light-emitting diodes were prepared using Te 4+ -doped (C 4 H 7 N 2 ) 2 SnCl 6 , revealing the potential of this material for lighting applications. This study provides new insight into the PL mechanism of Sn 4+ -based metal-halide hybrids and thus facilitates the design and development of eco-friendly light-emitting metal halides.