Dalian Chemical Institute and others have developed one-component warm white photoluminescent devices

Recently, Yang Bin, associate researcher of Dalian Institute of Chemical Physics, Chinese Academy of Sciences, and Liu Feng, a researcher at Shandong University, collaborated to develop a new double perovskite material with efficient white light emission, and prepared a one-component warm white light-emitting diode (LED)
based on the material.

Electric lighting accounts for 15% of global electricity consumption and releases 5% of the world's greenhouse gases
.
The use of more efficient and low-cost lighting technology can alleviate the energy and environmental crises and help achieve the "dual carbon" goal
.
At present, the vast majority of white LED technology mainly relies on blue LED excitation multi-component fluorescence superposition to produce white light, so it is easy to have problems such as
poor color rendering, low luminous efficiency, high harmful blue light components, and discontinuous white light spectrum.
The development of efficient one-component white light materials is considered to be the key
to solving these problems.

The researchers found that non-lead metal halide double perovskite materials can be prepared by cryogenic solution method with low
production cost.
In addition, due to the limitation of its own structure and the strong electro-phonon coupling effect, the double perovskite material has a unique self-trapping exciton characteristic (STE), and its composite luminescence shows a large Stokes shift and broadband light emission, thus showing the characteristics of
white light emission.
In this work, the researchers prepared a one-dimensional structure (DFPD)_2M^IInX₆(M^I = K, Rb; X = Cl, Br) double perovskite compound
.
Among them, DFPD⁺ not only acts as an effective interlayer spacer to balance the charge, but also as a key component in the formation of
metal halide octahedron.
(DFPD) ₂ The electron state in MⁱInX₆ is spatially confined to a single octahedron, creating a natural electron confinement effect
.
To facilitate radiation recombination, the researchers further employed a^microSb3+ doping strategy to increase the white light quantum efficiency from 5% to more than
90%.
Due to the high optoelectronic performance and excellent solution processability of the prepared low-dimensional double perovskite material, one-component warm white LEDs based on the material can be prepared by simple solution method, so this work provides new ideas
for the design of next-generation lighting devices.

In recent years, Yang Bin and other researchers have carried out systematic research in the field of self-trapping exciton-based one-component white light materials and their luminescence dynamics: revealing the exciton ultrafast self-trapping process (Angew.
Chem.
Int.
Ed.
, 2019; Acc.
Chem.
Res.
, 2019), and the influence mechanism of electro-phonon coupling on this ultrafast process (Sci.
Bull.
, 2020); The luminescence mechanism based on self-trapping exciton heat-activated delayed fluorescence was revealed (Angew.
Chem.
Int.
Ed.
, 2020); Efficient white light emission in colloidal nanocrystals was achieved through efficient energy transfer between the trilinear self-trapping exciton and the acceptor ion^{Mn 2+} (Nano Lett.
, 2021); Based on the unique properties of self-collapsed excitons, it expanded its role in long-afterglow luminescent materials (Angew.
Chem.
Int.
Ed.
, 2022), highly sensitive ultraviolet photodetectors (Adv.
Mater.
, 2021; Laser Photonics Rev.
, 2022), X-ray scintillators (J.
Phys.
Chem.
Lett.
, 2022; J.
Phys.
Chem.
Lett.
, 2022; Laser Applications in Photonics Rev.
, 2022), ultra-sensitive optical thermometers (J.
Phys.
Chem.
Lett.
, 2022
).

The research results were published in Highly Luminescent One-Dimensional Organic–Inorganic Hybrid Double-Perovskite-Inspired Materials for Single-Component Warm White-Light-Emitting Diodes Incorporated in German Applied Chemistry.
Angewandte Chemie International Edition
).
The above work is supported
by the National Natural Science Foundation of China, the Youth Innovation Promotion Association of the Chinese Academy of Sciences, and the Innovation Fund of Dalian Chemical Institute.

Dalian Chemical Institute and others have developed one-component warm white photoluminescent devices