Chinese scholars and overseas collaborators have made progress in the controllable preparation of perovskite quantum dot solid films

Figure: Perovskite quantum dot solid film strategy and constructed high-performance semiconductor device

With the support of the National Natural Science Foundation of China (approval numbers: 91956130, 62104116, 22121005), the scientific research team led by researcher Yuan Mingjian and Professor Chen Jun of Nankai University and the team of Professor Edward H.
Sargent of the University of Toronto have made progress
in the accurate controllable preparation of high-quality perovskite quantum dot solid films 。 The research results, titled "Synthesis-on-Substrate of Quantum Dot Solids", were published online in the journal
Nature on December 22, 2022.
Link to the paper: _istranslated="1">.

Quantum dots are one of the important materials for the reliable manufacturing of
high-performance optoelectronic devices.
In the synthesis of traditional colloidal quantum dots, in order to maintain their stability in solvents, a large number of organic ligands are introduced to the surface of quantum dots
.
However, the existence of organic ligands greatly hinders the transport efficiency of charge between quantum dots and limits its application potential
in many semiconductor optoelectronic devices.
Therefore, in-depth exploration of the formation mechanism of quantum dots and the dynamic transport and operation of carriers inside materials, and the development of "new materials, new processes, and new devices" are the inevitable requirements
for realizing high-performance quantum dot optoelectronic devices and promoting the technological innovation of semiconductor quantum dots.

Through the rational design of surface organic ligand chemical structure, the above research team developed a new strategy
for the preparation of high-performance conductive perovskite quantum dot solid films.
This strategy effectively avoids the problems of easy ligand shedding, poor optical performance and poor conductivity caused by too many ligands in traditional quantum dot preparation methods, and the synthesized perovskite quantum dot solid film has excellent optical and electrical properties
.
At the same time, the research team introduced the high-performance perovskite quantum dot solid film material into the electroluminescent diode device, and successfully realized the controllable construction of the three-color electroluminescent diode with high energy conversion efficiency (Figure).

This work helps people to understand the mechanism of organic ligands in the controllable regulation of physicochemical properties such as dimensional information, electronic band structure, and exciton effect of perovskite materials, and the developed in situ preparation strategy also provides a new idea
for the further application of perovskite quantum dot materials in other semiconductor optoelectronic devices.