Antimony doped tin(iv) hybrid metal halides with high-efficiency tunable emission, WLED and information encryption

Abstract

Although single-component white light emitting perovskites have emerged as a new star material with great potential in solid-state lighting, the synthesis of lead-free halide perovskites with high efficiency and high color rendering index (CRI) remains challenging. Here, we report a series of zero-dimensional antimony-doped tin(IV)-based hybrid metal halides (C₁₃H₃₀N)₂SnCl₆:x%Sb with wavelength-dependent tunable emission. (C₁₃H₃₀N)₂SnCl₆:20% Sb produces a strong white emission upon excitation at 325 nm, with nearly 100% photoluminescence quantum yield (PLQY), and produces bright red emission with 80.98% PLQY under 380 nm excitation at room temperature (RT). This profile shows that there are two types of emission centers, resulting from high-efficiency dual emission bands, one out of the self-trapped exciton (STE) of ³P₁ to ¹S₀ from SbCl₆ octahedra with green emission at 510 nm, and another due to the radiative recombination of the STE of ³P₁ to ¹S₀ from the SbCl₅ pyramid with broad red emission around 666 nm, which also contain some DAP (D-donor, A-acceptor, P: pair) transitions around 740 nm between Sb and Sn sites. The single-component light-emitting diode (LED) device based on (C₁₃H₃₀N)₂SnCl₆:20% Sb has an excellent color rendering index as high as 96.7, and the corresponding color coordinates are (0.346, 0.380). The excitation wavelength-dependent tunable emission profile makes (C₁₃H₃₀N)₂SnCl₆:x%Sb a high-performance material for applications in single component white light-emitting diodes (WLEDs), anti-counterfeiting, information encryption, and flexible lighting displays.