CN-122003019-A - X-ray detector based on narrow-band-gap perovskite and wide-band-gap perovskite heterojunction and preparation method thereof

CN122003019ACN 122003019 ACN122003019 ACN 122003019ACN-122003019-A

Abstract

The invention discloses an X-ray detector based on a narrow-band-gap perovskite and a wide-band-gap perovskite heterojunction and a preparation method thereof, and belongs to the technical field of perovskite. The X-ray detector based on the narrow-band-gap perovskite and the wide-band-gap perovskite heterojunction comprises a metal electrode layer, a rare earth oxide layer, a three-dimensional narrow-band-gap perovskite layer-three-dimensional wide-band-gap perovskite layer heterojunction, a rare earth oxide layer and a metal electrode layer which are sequentially stacked. The active layer in the X-ray detector based on the narrow-band-gap perovskite and the wide-band-gap perovskite heterojunction is a three-dimensional narrow-band-gap perovskite layer-three-dimensional wide-band-gap perovskite layer heterojunction, and the perovskite heterojunction has the characteristics of low dark current, low defects, high carrier transmission performance, high sensitivity, quick response time and the like, so that the performances of sensitivity, mobility, service life product and the like of the X-ray detector are improved.

Inventors

XIAO SHUANG
XUE BIN
DENG ZIXIN
Xing Leting

Assignees

深圳技术大学

Dates

Publication Date: 20260508
Application Date: 20260305

Claims (9)

1. An X-ray detector based on narrow-band-gap perovskite and wide-band-gap perovskite heterojunction is characterized by comprising a metal electrode layer, a rare earth oxide layer, a three-dimensional narrow-band-gap perovskite layer-three-dimensional wide-band-gap perovskite layer heterojunction, a rare earth oxide layer and a metal electrode layer which are sequentially stacked.
2. The X-ray detector based on narrow bandgap perovskite and wide bandgap perovskite heterojunction according to claim 1, wherein the metal electrode layers are all chromium metal electrode layers; the rare earth oxide layers are all erbium oxide layers; the three-dimensional narrow band gap perovskite layer-three-dimensional wide band gap perovskite layer heterojunction comprises a bromine lead tin methylamine perovskite layer and a three-dimensional wide band gap perovskite layer.
3. The X-ray detector based on narrow bandgap perovskite and wide bandgap perovskite heterojunction according to claim 2, wherein the thickness of the metal electrode layers is 120nm; the thickness of the rare earth oxide layers is 100nm; The thickness of the three-dimensional narrow band gap perovskite layer-three-dimensional wide band gap perovskite layer heterojunction is 2.5mm, wherein the thickness of the three-dimensional narrow band gap perovskite layer is 0.5mm-1mm, and the thickness of the three-dimensional wide band gap perovskite layer is 1-1.5mm.
4. A method of manufacturing an X-ray detector based on a narrow bandgap perovskite and a wide bandgap perovskite heterojunction as claimed in any one of claims 1 to 3, comprising the steps of: s1, putting a wide-band-gap perovskite crystal into a narrow-band-gap perovskite precursor solution, and growing a narrow-band-gap perovskite on the surface of the wide-band-gap perovskite crystal by using a reverse temperature crystallization method to form a heterostructure; S2, cutting and polishing the heterostructure to obtain a three-dimensional narrow-band-gap perovskite layer-three-dimensional wide-band-gap perovskite layer heterojunction; S3, sequentially evaporating a rare earth oxide layer and a metal electrode layer on the top and bottom surfaces of the three-dimensional narrow-band-gap perovskite layer-three-dimensional wide-band-gap perovskite layer heterojunction, and preparing the X-ray detector based on the narrow-band-gap perovskite and wide-band-gap perovskite heterojunction.
5. The preparation method of the lead-bromide perovskite single crystal according to claim 4, wherein in the step S1, the wide-bandgap perovskite single crystal is a lead-bromide perovskite single crystal, and the preparation method of the lead-bromide perovskite single crystal comprises the steps of adding isopropanol into a mixed organic solution of lead bromide and methyl amine bromide, uniformly stirring, filtering to obtain a precursor solution, heating for the first time to obtain a seed crystal, and placing the seed crystal into a homogeneous precursor solution and heating for the second time to obtain the lead-bromide perovskite single crystal.
6. The method according to claim 5, wherein the ratio of the amounts of lead bromide, methyl amine bromide and isopropyl alcohol is 4.59 g/1.388 g/100 uL; The temperature of the first heating is 90 ℃; the temperature of the secondary heating is 44-52 ℃.
7. The preparation method of the lead tin methyl amine perovskite according to claim 4, wherein in the step S1, the narrow-band gap perovskite precursor solution is a lead tin methyl amine perovskite precursor solution, and the preparation method of the lead tin methyl amine perovskite precursor solution comprises the following steps of mixing lead tin methyl amine perovskite powder, tin powder and formamidine sulfine D salt with N, N-dimethylformamide, introducing argon, stirring, dissolving and filtering to obtain the lead tin methyl amine perovskite precursor solution.
8. The method according to claim 7, wherein the ratio of the amount of the bromoplumbum-stannum-methylamine perovskite powder, the tin powder, the formamidine sulfinate D salt and the N, N-dimethylformamide is 4.5 g/20 mg/25 mg/6 mL.
9. The method according to claim 4, wherein in step S1, the temperature of the reverse temperature crystallization method is 32-40 ℃.

Description

X-ray detector based on narrow-band-gap perovskite and wide-band-gap perovskite heterojunction and preparation method thereof Technical Field The invention belongs to the technical field of perovskite, and particularly relates to an X-ray detector based on a narrow-band-gap perovskite and a wide-band-gap perovskite heterojunction and a preparation method thereof. Background The halide perovskite is used as an emerging semiconductor material system, and has a huge application prospect in the field of photoelectric devices due to a unique crystal structure and excellent photoelectric properties. The halide perovskite has the characteristics of direct band gap, strong light absorption coefficient, long carrier diffusion length, low defect state density and the like, and has been widely applied to the fields of solar cells, light-emitting diodes, photodetectors and the like. In contrast, the development of perovskite-based X-ray detectors in terms of optoelectronic performance improvement and device engineering is still at a relatively early stage. Meanwhile, perovskite materials show important application potential in the X-ray detection direction. Compared with the traditional amorphous selenium (alpha-Se), silicon-based or cadmium telluride detector with the advantages of mature process, lower dark current and the like, the perovskite has high atomic number element composition and high photoelectric absorption efficiency, can realize stronger X-ray absorption and higher charge collection efficiency under the same thickness, and shows obvious advantages in key performance indexes such as sensitivity, response time, mobility life Product (mu tau Product) and the like. However, the existing perovskite heterojunction X-ray detector still has a large improvement space in terms of sensitivity, response speed and mobility life product. Disclosure of Invention Aiming at the problems, the invention provides an X-ray detector based on a narrow-band-gap perovskite and a wide-band-gap perovskite heterojunction and a preparation method thereof. In order to achieve the aim of the invention, the invention adopts the following technical scheme: In a first aspect, the invention provides an X-ray detector based on a narrow bandgap perovskite and a wide bandgap perovskite heterojunction, which comprises a metal electrode layer, a rare earth oxide layer, a three-dimensional narrow bandgap perovskite layer-three-dimensional wide bandgap perovskite layer heterojunction, a rare earth oxide layer and a metal electrode layer which are sequentially stacked. Further, the metal electrode layers are chromium metal electrode layers, the rare earth oxide layers are erbium oxide layers, the three-dimensional narrow band gap perovskite layers in the three-dimensional narrow band gap perovskite layer-three-dimensional wide band gap perovskite layer heterojunction are bromine lead tin methylamine perovskite layers (MAPb xSn1-xBr3), and the three-dimensional wide band gap perovskite layers are bromine lead methylamine perovskite layers (MAPbBr 3). Further, the thicknesses of the metal electrode layers are 120nm, the thicknesses of the rare earth oxide layers are 100nm, the thickness of the three-dimensional narrow band gap perovskite layer-three-dimensional wide band gap perovskite layer heterojunction is 2.5mm, the thickness of the three-dimensional narrow band gap perovskite layer is 0.5mm-1mm, and the thickness of the three-dimensional wide band gap perovskite layer is 1-1.5mm. In a second aspect, the invention provides a method for preparing the X-ray detector based on the narrow-bandgap perovskite and the wide-bandgap perovskite heterojunction, which comprises the following steps: s1, putting a wide-band-gap perovskite crystal into a narrow-band-gap perovskite precursor solution, and growing a narrow-band-gap perovskite on the surface of the wide-band-gap perovskite crystal by using a reverse temperature crystallization method to form a heterostructure; S2, cutting and polishing the heterostructure to obtain a three-dimensional narrow-band-gap perovskite layer-three-dimensional wide-band-gap perovskite layer heterojunction; S3, sequentially evaporating a rare earth oxide layer and a metal electrode layer on the top and bottom surfaces of the three-dimensional narrow-band-gap perovskite layer-three-dimensional wide-band-gap perovskite layer heterojunction, and preparing the X-ray detector based on the narrow-band-gap perovskite and wide-band-gap perovskite heterojunction. The invention provides a preparation method of a narrow band gap perovskite and a wide band gap perovskite heterojunction, which comprises the steps of after preparing a narrow band gap perovskite precursor solution, placing a wide band gap perovskite monocrystal in the precursor solution, directly contacting the solution with the surface of the wide band gap perovskite monocrystal, and separating out the narrow band gap perovskite crystal on the surface of the wide band