High-efficiency red photoluminescence achieved by antimony doping in organic–inorganic halide (C11H24N2)2[InBr6][InBr4]. Issue 15 (18th March 2022)

• Record Type: Journal Article
• Authors: Lin, Jiawei; Guo, Zhongnan; Sun, Niu; Liu, Kunjie; Chen, Xin; Zhao, Jing; Liu, Quanlin; Yuan, Wenxia
• Is Part Of: Journal of materials chemistry. Volume 10:Issue 15(2022)
• Page Start: 5905
• Page End: 5913
• Publication Date: 2022-03-18
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d2tc00355d
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : We report a new 0D lead-free halide with both [InBr6 ] 3− octahedra and [InBr4 ] − tetrahedra as inorganic units. High-efficiency red photoluminescence can be achieved via Sb doping in this emissive material with a PLQY of 61%. Abstract : Organic–inorganic metal halides (OIMHs) exhibit various crystal structures and strong broadband emission, showing enormous potential for solid-state lighting and displays. In this work, we report a new lead-free OIMH (C11 H24 N2 )2 [InBr6 ][InBr4 ], which adopts a typical zero dimensional (0D) structure with the inorganic polyhedra separated by the large organic cations. Different from the general 0D In-based OIMHs with single octahedral [InBr6 ] 3− units, (C11 H24 N2 )2 [InBr6 ][InBr4 ] contains both [InBr6 ] 3− octahedra and [InBr4 ] − tetrahedra. It shows a large optical bandgap of 3.95 eV and excellent ambient stability. In addition, Sb dopants can be included in the structure, and an obvious preference for substituting the In atoms in the [InBr6 ] 3− octahedra has been determined by analyzing the related bond lengths and polyhedral distortion. (C11 H24 N2 )2 [InBr6 ][InBr4 ] exhibits a broadband red emission (660 nm) that is ascribed to self-trapped excitons (STEs) in octahedral [InBr6 ] 3−, and the photoluminescence quantum yield (PLQY) can be significantly enhanced from 8% to 61% upon Sb doping, mainly as a result of the extra photo-induced excitons from [SbBr6 ] 3− . Density functional calculations reveal the direct bandgap nature of (C11 H24 N2 )2 [InBr6 ][InBr4 ], which is transferred to an indirect band gap after Sb doping due to the formation of the intra-gap band. A white light-emitting diode (WLED) was fabricated by combining the red emissive (C11 H24 N2 )2 [InBr6 ][InBr4 ]:Sb 3+ and commercial green and blue phosphors, exhibiting a high color-rendering index of 88.7. Our work reports high-efficiency red photoluminescence (PL) in this special 0D double-inorganic-unit system, and demonstrates its potential applications for solid-state lighting.