Realizing Tunable White Light Emission in Lead-Free Indium(III) Bromine Hybrid Single Crystals through Antimony(III) Cation Doping

Abstract

Low-dimensional metal halide hybrids (OIMHs) have recently been explored as single-component white-light emitters for use in solid-state lighting. However, it still remains challenging to realize tunable white-light emission in lead-free zero-dimensional (0D) hybrid system. Here, a combination strategy has been proposed through doping Sb 3+ enabling and balancing multiple emission centers toward the multiband warm white light. We first synthesized a new lead-free 0D (C 8 NH 12 ) 6 InBr 9 •H 2 O single crystal, in which isolated [InBr 6 ] 3− octahedral units are separated by large organic cations [C 8 NH 12 ] + . (C 8 NH 12 ) 6 InBr 9 •H 2 O exhibits dual-band emissions with one intense cyan emission and a weak red emission tail. The low-energy ultrabroadband red emission tail can be greatly enhanced by the Sb 3+ doping. Experimental data and first-principles calculations reveal that the original dominant cyan emission is originated from the organic cations [C 8 NH 12 ] + and that the broadband red emission is ascribed to selftrapped excitons in [In(Sb)Br 6 ] 3− . When the Sb concentration is 0.1%, a single-component warm white-light emission with a photoluminescence quantum efficiency of 23.36%, correlated color temperature of 3347 K, and a color rendering index up to 84 can be achieved. This work represents a significant step toward the realization of single-component white-light emissions in environmental-friendly, high-performance 0D metal halide light-emitting materials.

Indium-antimony-halide single crystals for high-efficiency white-light emission and anti-counterfeiting

“…Three-dimensional (3D) organic-inorganic lead halide perovskites have gained tremendous attention due to their unique optical and electronic properties, such as high absorption coefficiency, easily tunable bandgaps, high charge carrier mobility, and exceptional defect tolerance, which further enable their successful implementation in solar cells, photodetectors, and light-emitting diodes (LEDs) (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12). Very recently, low-dimensional lead halide perovskites have emerged as single-phase white-emitting materials due to their intriguing broadband emission behavior, which has been highlighted with excellent color stability and can efficiently avert self-absorption issues faced by the currently commercial multicomponent-based white-light sources (13)(14)(15)(16)(17)(18)(19)(20).…”

White-light defect emission and enhanced photoluminescence efficiency in a 0D indium-based metal halide

“…Luminescent lead-free indium (In)-based materials have attracted growing interest recently due to their air and photo-stability and the excellent optoelectronic properties. 9,20,46–52 In contrast to ns 2 -metals with an outer-shell lone pair, In 3+ has a filled 4d 10 5s 0 electron configuration, which makes its compound as an ideal prototype to unveil the intriguing photophysical mechanism. Thus, in this work, we concentrate on the broad emission from 0D In 3+ -based halides.…”

Emerging new‐generation white light‐emitting diodes based on luminescent lead‐free halide perovskites and perovskite derivatives

“…Another potential candidate for the substitution of lead in the perovskite structure is the group-13 element Indium. [73][74][75][76][77] In comparison to Pb 2+ , the trivalent In 3+ has a relatively small atomic volume, and thus this heterovalent substitution tends to form a low-dimensional structure. [78][79][80] Kuang et al first reported the zerodimensional In-based perovskites Cs 2 InCl 5 •H 2 O and (C 4 H 14 N 2 ) 2 In 2 Br 10 , which presented red broadband emission with PLQY of 33% and 3%, respectively.…”

“…Similarly, Xie et al reported a Sb-doped (C 8 NH 12 ) 6 InBr 9 •H 2 O single crystal, which exhibited a warm white-light emission with a PLQY of 23.36%, a CCT of 3347 K, and a CRI of 84. [76] Later, Chen and co-workers synthesized another In-based (C 6 H 5 CH 2 NH 3 ) 3 InBr 6 perovskite that shows a broadband orange emission with an ultra-large Stokes shift of 245 nm and a FWHM of 132 nm (Figure 7E). [77] The use of such materials as down-converters has a great potential to overcome the problems observed in the conventional WLEDs based on mixed phosphors, such as the efficiency losses due to self-absorption and the changes of the white light quality over time due to different aging of mixed phosphors.…”