Zero-Dimensional Hybrid Indium Halides with Efficient and Tunable White-Light Emissions

Abstract

Two-dimensional hybrid lead perovskites have attracted a great deal of attention in white-light-emitting diodes, but the serious toxicity of Pb2+ and the limited photoluminescence quantum yield (PLQY) still restrict further optoelectronic application. To address these issues, a new combining photon strategy was proposed to achieve highly efficient broadband white-light emission in a new family of zero-dimensional (0D) indium halides based on an [InCl6]3– octahedron. Remarkably, these 0D halides display dual-band white-light emission derived from the synergistic work of blue- and yellow-light-emitting bands, which can be ascribed to the radiative recombination of bound excitons in organic cations and self-trapped excitons in inorganic anions, respectively, based on spectroscopy and theoretical studies. In-depth first-principles calculation demonstrates that the increased structural deformability effectively improves the PLQY from 7.01% to 18.56%. As a proof of concept, this work provides a profound understanding for advancing the rational design of novel single-component 0D lead-free halides as high-performance white-light emitters.

Intrinsic vs. extrinsic STE emission enhancement in ns2 ion doped metal (Cd, In) halide hybrids

“…The faster decay time indicates a singlet to singlet relaxation in the host system (in contrast to the triplet to singlet relaxation for the 560 nm emission band of the host system). 44–51 Interestingly, the AEPipInSbCl doped system shows a uniform broadband emission peak centred at 560 nm across different excitation wavelengths (250–400 nm) at room temperature (Fig. 4c).…”

“…Such weak broad emission in 0D In halide hybrids has been previously ascribed to STE based emission. 44–51 The PLE profile across the emission bands of the host system also vary signifying different emissive mechanisms for the high energy and low energy emission bands (Fig. 4b) for the host.…”

High-Efficiency Intrinsic Yellow-Orange Emission in Hybrid Indium Bromide with Double Octahedral Configuration

“…Among the 0D lead-free OIMH family, In-based OIMHs with discrete indium–halide polyhedrons have received more interest recently as promising emitters owing to their excellent air stability, low toxicity, and tunable emissions. − Zhou et al reported a 0D In-based hybrid (C 4 H 14 N 2 ) 2 In 2 Br 10 with red emission, which structurally consisted of [InBr 4 ] − tetrahedra and [InBr 6 ] 3– octahedra units, but only the octahedral units acted as luminescent centers . Subsequently, Chen et al synthesized 0D (PMA) 3 InBr 6 (PMA = phenylmethylammonium), which showed orange emission with a relatively high PLQY of 35% .…”

Reversible Luminescent Switching Induced by Heat/Water Treatment in a Zero-Dimensional Hybrid Antimony(Ⅲ) Chloride

“…In addition, 0-D IOMHs may own soft lattice and strong electron–phonon coupling, thus leading to interesting photoluminescent properties, including broad emission and large Stokes shift [ 10 ]. As a result, the applications of photoluminescent 0-D IOMHs have flourished in light-emitting diode [ 11 , 12 , 13 , 14 , 15 ], X-ray scintillator [ 16 , 17 , 18 ], remote thermography [ 19 , 20 ], optical waveguide [ 21 ], anti-counterfeiting [ 22 , 23 , 24 , 25 , 26 ], as well as sensor [ 27 , 28 , 29 , 30 ].…”