A Lead‐Free All‐Inorganic Metal Halide with Near‐Unity Green Luminescence

Abstract

As the increasing demand of lighting display technology, environmentallyfriendly, economic light-emitting materials with high performance are required. Herein, a novel solution-processed, highly emissive copper chloride compound -Cs 3 Cu 2 Cl 5 is reported. The crystal structure determined by the Rietveld refinement of the powder X-ray diffraction patterns shows that the corner-sharing tetrahedral Cu-Cl chains are surrounded by Cs + cations, yielding a one-dimensional structure at molecular level. The all-inorganic compound shows excellent photostability, and is thermally stable up to 550°C. Excitingly, it exhibits room-temperature photoluminescence in the green region with near-unity quantum yield. Currently, this appears to be the most efficient lead-free all-inorganic green-light emitting metal halides reported.

A Highly Efficient and Stable Blue‐Emitting Cs5Cu3Cl6I2 with a 1D Chain Structure

“…The Rietveld refinement of the powder XRD pattern indicated that Cs 3 Cu 2 Cl 5 adopts space group Cmcm ( a = 15.449[5] Å, b = 8.7562[3] Å, and c = 8.6814[3] Å) (see Tables S8–S10, Supporting Information), which is different from the I and Br analogs ( Pnma ), as shown in Figure 1d,e. [ 21–23 ] For the Cs 3 Cu 2 Cl 5 , each Cu + ion has been coordinated with three Cl − ions and adopted a near‐planar configuration. Through Cl corner sharing, two [CuCl 3 ] 2− units formed an isolated folded dimer [Cu 2 Cl 5 ] 3− with a 75.51° face angle.…”

“…Notably, the localized holes, not the electrons, play a crucial role for STE emission, which is substantiated by the observance of distinct flat valence bands for all the efficient copper(I) halide emitters, such as Cs 3 Cu 2 I 5 (0D), Cs 3 Cu 2 Cl 5 (0D/quasi‐1D), Cs 5 Cu 3 Cl 6 I 2 (1D), CsCu 2 Cl 3 (1D), and Rb 2 CuCl 3 (1D). [ 9,15,22,29 ]…”

Structural phase evolved Ni2+‐doped fluoride nanocrystals in KF−ZnF2−SiO2 glass‐ceramics

“…The optical detector was a SPT counting module. 25 The emitting ratios described by the number of probed over shot photons were obtained. All experiments were performed at room temperature except EPR.…”

Mn2+ Induced Significant Improvement and Robust Stability of Radioluminescence in Cs3Cu2I5 for High Performance Nuclear Battery

“…Besides, the concentration of chloride ion cannot be too high due to the intrinsic lattice instability. 33 The lattice expansion with increased Mn 2+ concentration can be assigned to the larger ion radius of Mn 2+ . 34 When doping concentration increases to 25%, the diffraction peak shifts back to a higher degree, indicating the saturation of Mn 2+ and lattice instability at high doping concentration, which will lead to poor optical properties undoubtedly.…”