Zero-dimensional lead-free caesium copper iodine perovskite blue nanocrystal and preparation method thereof

Abstract

The invention relates to a zero-dimensional lead-free caesium copper iodine perovskite blue nanocrystal and a preparation method thereof, and belongs to the technical field of photoelectron material preparation. The preparation method of the nanocrystal comprises the steps that cesium iodide and cuprous iodide are dissolved in N,N-dimethylformamide or dimethyl sulfoxide to obtain a precursor solution, then the precursor solution is injected into an organic solution, a stirring reaction is performed for 3-6 minutes at a speed of 5000-9000 rpm, then centrifugation is preformed, a precipitate istaken and washed, and the nanocrystal is obtained. The nanocrystal not only has a good crystal structure, high yield, high fluorescence efficiency and a stable structure, but also contains no heavy metal lead, reduces the harm to the human body and the environment, and has wide application prospects in photovoltaic devices. The preparation method of the nanocrystal is simple and easy to implement,has low cost and can be popularized in the industrial production.

Description

technical field [0001] The invention belongs to the technical field of optoelectronic material preparation, and in particular relates to a zero-dimensional lead-free cesium copper iodine perovskite blue light nanocrystal and a preparation method thereof. Background technique [0002] As a new type of inorganic functional material, all-inorganic lead-halide perovskite nanomaterials have broad application prospects in solar cells, light-emitting diodes, and micro-lasers with excellent optical and electrical properties. Although the preparation of all-inorganic lead halide perovskite nanomaterials has made great progress, there are still the following problems: 1. The lack of high-performance blue-light nanocrystal luminescent materials, and the current emission wavelength of lead halide perovskite nanocrystals is limited. Tuning depends on the type of halogen atoms, and lead halide perovskite nanocrystals usually have low luminous efficiency (PLQY<30%) and poor thermal stab...

AI Technical Summary

Problems solved by technology

Although the preparation of all-inorganic lead halide perovskite nanomaterials has made great progress, there are still the following problems: 1. The lack of high-performance blue-light nanocrystal luminescent materials, and the current emission wavelength of lead halide perovskite nanocrystals is limited. Tuning depends on the type of halogen atoms, while lead halide perovskite nanocrystals usually have low luminous efficiency (PLQY<30%) and poor thermal stability

Although the emission wavelength of lead-bromine flake nanocrystals can be shifted from green light to blue light, the system is prone to orientation adsorption under light, forming aggregates, resulting in red shift of blue light.

2. The anion exchange reaction between different halogen perovskite nanocrystals, although the adjustment of the luminous range from blue light to red light is realized, it also brings a series of problems such as spectral broadening and chromaticity drift.

3. Lead halide perovskite contains heavy metal lead, which is harmful to the human body and the environment, which limits its future application in the field of light-emitting displays

Therefore, the existing technology for preparing all-inorganic lead halide perovskite nanomaterials still needs to be improved and developed, and low-toxicity and high-efficiency blue light nanomaterials need to be excavated urgently

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