Preparation method of manganese-doped copper-based halide perovskite powder
Technical Field
The invention relates to a manganese-doped copper-based halide perovskite and a preparation method thereof, belonging to the field of photoelectric functional materials.
Background
In recent years, halide perovskites are considered to be good candidate materials for next-generation light-emitting devices due to the advantages of simple preparation method, low cost, easy regulation and control of light emission and the like. The traditional lead-based halide perovskites have certain limitations in practical application due to poor stability and toxicity of lead elements. Copper-based halide perovskites are believed to be expected to address both of these issues while maintaining a high fluorescence quantum yield of lead-based halide perovskites. There are two main approaches to fluorescence modulation of halide perovskites: (1) the energy gap is adjusted by changing the halogen composition, so that the intrinsic fluorescence peak position is changed; (2) impurity level is introduced by doping to realize impurity fluorescence. Both of these methods have certain difficulties in copper-based halide perovskites: halogen exchange can greatly reduce the fluorescence quantum yield, and the fluorescence regulation range is far smaller than that of lead-based halide perovskite. Cation doping is realized at a high temperature of 450 ℃, the process is complex and the cost is increased. Therefore, a new doping method needs to be provided, which can realize the doping of cations and reduce the reaction temperature, so as to realize the low-cost regulation and control of the luminescence of the copper-based halide perovskite.
Disclosure of Invention
The invention aims to provide manganese-doped copper-based halide perovskite powder and a preparation method thereof, which can reduce the temperature required by doping and realize the fluorescence regulation and control of the copper-based halide perovskite by manganese doping.
In order to achieve the purpose, the invention adopts the technical scheme that:
a process for preparing the Mn-doped Cu-base halide perovskite powder (Mn: Cs)3Cu2I5The preparation method comprises the following steps:
(1) preparation of copper-based halide perovskite Cs3Cu2I5: mixing cesium iodide powder and cuprous iodide powder, and then fully grinding to obtain copper-based halide perovskite powder;
(2) preparation of manganese-doped copper-based halide perovskite Mn: Cs3Cu2I5: and (2) mixing the copper-based halide perovskite powder prepared in the step (1) with manganese chloride tetrahydrate, and then fully grinding to obtain manganese-doped copper-based halide perovskite powder.
In the step (1), the stoichiometric ratio of cesium iodide powder to cuprous iodide powder is 3: 2.
In the step (2), the dosage of the manganese chloride tetrahydrate is 0-15% in terms of Mn/Cu molar ratio, but 0% is not included.
In the steps (1) and (2), the grinding time is more than 20 minutes.
In the steps (1) and (2), the grinding is one of the following three grinding modes: (a) grinding by adding raw materials only, (b) grinding by adding raw materials and silicon dioxide powder, (c) grinding by adding raw materials and 10-50 ml of buffer solution.
The buffer solution is one of n-hexane, toluene and octadecene; if octadecene is added as buffer for grinding, it is necessary to wash for 2-3 times with n-hexane and then dry, and if n-hexane or toluene is added as buffer for grinding, it is dried directly.
Has the advantages that: compared with the prior art, the manganese-doped copper-based halide perovskite and the preparation method thereof provided by the invention have the following advantages:
(1) the method has the advantages of simple operation, high material utilization rate, small dependence on equipment and short preparation period;
(2) the copper-based halide perovskite powder with higher fluorescence quantum yield can be produced in large batch;
(3) the doping of manganese can introduce an impurity fluorescence peak with a peak value at 540 nm;
(4) the relative intensity of the intrinsic fluorescence peak and the impurity fluorescence can be adjusted by changing the feed ratio of manganese.
Drawings
FIG. 1 is a graph showing the results of fluorescence spectrum characterization of copper-based halide perovskite powders of different manganese doping concentrations prepared in examples 1 to 5;
FIG. 2 is a CIE coordinate diagram corresponding to the fluorescence spectra of copper-based halide perovskite powders with different manganese doping concentrations prepared in examples 1-5 and an application example of the copper-based halide perovskite powders as color conversion layers for light emitting diodes;
FIG. 3 is a graph showing the X-ray diffraction spectrum characterization results of copper-based halide perovskites of different manganese doping concentrations prepared in examples 1-5;
FIG. 4 is an X-ray photoelectron spectroscopy characterization of manganese-doped copper-based halide perovskites prepared in example 2 at a Mn/Cu molar ratio of 7.5% doping concentration;
FIG. 5 is a scanning electron microscopy characterization of manganese-doped copper-based halide perovskites prepared in example 2 at a Mn/Cu molar ratio of 7.5% doping concentration;
FIG. 6 is a schematic diagram of a manganese doped copper-based halide perovskite energy level structure;
FIG. 7 is a schematic process flow diagram of the preparation method of the present invention.
Detailed Description
The invention is explained in more detail below with reference to exemplary embodiments and the accompanying drawings.
Example 1
Preparation of undoped copper-based halide perovskite powder: 77.94 mg cesium iodide was mixed with 38.09 mg cuprous iodide and directly ground for 25 minutes to obtain copper-based halide perovskite powder.
Example 2
(1) Preparation of copper-based halide perovskite powder: mixing 77.94 mg of cesium iodide and 38.09 mg of cuprous iodide, and directly grinding for 25 minutes to obtain copper-based halide perovskite powder;
(2) preparing manganese-doped copper-based halide perovskite powder: and (3) adding 3 mg of manganese chloride tetrahydrate (the molar ratio of Mn to Cu is 7.5%) into the prepared copper-based lead-free perovskite powder, mixing, adding 30ml of n-hexane, grinding for 30 minutes, filtering and drying the suspension to obtain the manganese-doped copper-based lead-free perovskite powder.
Example 3
(1) Preparation of copper-based halide perovskite powder: mixing 779.4 mg of cesium iodide and 380.9 mg of cuprous iodide, and directly grinding for 25 minutes to obtain copper-based lead-free perovskite powder;
(2) preparing manganese-doped copper-based halide perovskite powder: and taking the prepared copper-based lead-free perovskite powder, adding 19.8 mg of manganese chloride tetrahydrate (the molar ratio of Mn/Cu is 5%), mixing, adding 30ml of n-hexane, grinding for 30 minutes, filtering and drying the suspension to obtain the manganese-doped copper-based lead-free perovskite powder.
Example 4
(1) Preparation of copper-based halide perovskite powder: mixing 1558.8 mg of cesium iodide and 761.8 mg of cuprous iodide, directly adding 20mL of toluene, grinding for 30 minutes, filtering and drying the suspension to obtain copper-based lead-free perovskite powder;
(2) preparing manganese-doped copper-based halide perovskite powder: and (3) adding 79.2 mg of tetrahydrated manganese chloride (the molar ratio of Mn to Cu is 10%) into the prepared copper-based lead-free perovskite powder, mixing, adding 20mL of toluene, grinding for 30 minutes, filtering and drying the suspension to obtain the manganese-doped copper-based lead-free perovskite powder.
Example 5
(1) Preparation of copper-based halide perovskite powder: mixing 3897 mg of cesium iodide and 1904.5 mg of cuprous iodide, directly adding 10mL of octadecene, grinding for 30 minutes, cleaning the suspension with n-hexane for 2 times, filtering, and drying to obtain copper-based lead-free perovskite powder;
(2) preparing manganese-doped copper-based halide perovskite powder: and adding 296.7 mg of manganese chloride tetrahydrate (the molar ratio of Mn to Cu is 15%) into the prepared copper-based lead-free perovskite powder, mixing, adding 10mL of octadecene, grinding for 30 minutes, cleaning the suspension with n-hexane for 2 times, filtering and drying to obtain the manganese-doped copper-based lead-free perovskite powder.
The above description is only of the preferred embodiments of the present invention, and it should be noted that: it will be apparent to those skilled in the art that various modifications and adaptations can be made without departing from the principles of the invention and these are intended to be within the scope of the invention.