An antimony-chromium co-doped halide perovskite and a preparation method and application thereof

Abstract

The application discloses a kind of antimony-chromium co-doped halide perovskite and its preparation method and application, belong to photoelectric functional material technical field.The chemical general formula of antimony-chromium co-doped halide perovskite described in the application is as follows: Cs3Bi 1‑x1‑x2 Sb x1 Cr x2 Cl6, the preparation method of the antimony-chromium co-doped halide perovskite is as follows: according to the chemical general formula, raw materials: CsCl, BiCl3, SbCl3 and CrCl3 are weighed: CsCl, BiCl3, SbCl3 are fully ground and mixed before sintering, after sintering, CrCl3 is added again, fully ground, to obtain antimony-chromium co-doped halide perovskite, all raw materials can also be ground together to obtain antimony-chromium co-doped halide perovskite after sintering.The halide perovskite described in the application has excellent near-infrared luminescence performance.

Description

Technical Field

[0001] This invention relates to an antimony-chromium co-doped halide perovskite, its preparation method, and its application, belonging to the field of optoelectronic functional materials technology. Background Technology

[0002] In recent years, halide perovskite materials have attracted widespread attention in the field of optoelectronic devices due to their excellent optical properties. Near-infrared luminescent materials, in particular, have significant application value in night vision, medical imaging, and information security. However, traditional near-infrared luminescent materials (such as rare-earth ion-doped materials) typically suffer from problems such as low luminous efficiency, high synthesis difficulty, and high cost.

[0003] Transition metal ions Cr 3+ Due to its dd-electronic transition characteristics, it has become an important choice for realizing near-infrared emission. However, direct doping of Cr into low-dimensional halide perovskites (such as Cs3BiCl6) is also problematic. 3+ This will create weak-field luminescence centers, resulting in low luminescence intensity. Therefore, how to optimize Cr... 3+ Near-infrared luminescence efficiency in the Cs3BiCl6 system has become a key research issue.

[0004] In existing technologies, achieving co-doping of two metal ions faces multiple challenges, including: differences in solubility between different ions can easily lead to phase separation, affecting material homogeneity; difficulties in energy level matching may reduce energy transfer efficiency and induce nonradiative recombination; the valence state modulation of dopant ions is complex, affecting luminescence performance; the optimal doping ratio is difficult to determine, and excessively high concentrations can easily induce quenching effects; simultaneously, precise control of reaction conditions is required during preparation to ensure the stability of material structure and optical properties. These problems limit the further application of co-doped systems in the near-infrared luminescence field. Summary of the Invention

[0005] To address the low near-infrared luminescence efficiency of existing halide perovskites, one objective of this invention is to provide an antimony-chromium co-doped halide perovskite, wherein the general chemical formula of the antimony-chromium co-doped halide perovskite is: Cs3Bi 1-x1-x2 Sb x1 Cr x2 Cl6, where x1 = 0.01 to 0.2 and x2 = 0.01 to 0.2.

[0006] Another object of the present invention is to provide a chemical formula Cs3Bi 1-x1-x2 Sb x1 Cr x2Preparation method of antimony-chromium co-doped halide perovskite of Cl6: Weigh the raw materials according to the stoichiometric ratio in the general chemical formula: CsCl, BiCl3, SbCl3 and CrCl3. First, grind and mix CsCl, BiCl3 and SbCl3 thoroughly and then sinter them. After sintering, add CrCl3 and grind thoroughly to obtain antimony-chromium co-doped halide perovskite. This method is a two-step method.

[0007] This invention also provides another method for preparing antimony-chromium co-doped halide perovskite: weigh the raw materials according to the stoichiometric ratio in the general chemical formula: CsCl, BiCl3, SbCl3 and CrCl3, grind the raw materials thoroughly and sinter them to obtain antimony-chromium co-doped halide perovskite. This method is a one-step method.

[0008] Preferably, the sintering temperature is 300℃~400℃ and the sintering time is 1.5~2 hours.

[0009] The present invention relates to the application of antimony-chromium co-doped halide perovskites in infrared detection and imaging, optical communication and encryption, biomarking and phototherapy, or infrared LEDs and lasers.

[0010] This invention uses Cs3BiCl6 as the matrix and dopes it with Sb. 3+ and Cr 3+ Formation of Cs3Bi 1-x1-x2 Sb x1 Cr x2 Cl6 structure; Sb 3 + Doping can force Cr 3+ Occupy lattice sites conducive to light emission and optimize the light emission center; employ a two-step doping method, first doping with Sb. 3+ Add Cr 3 + This can further improve near-infrared luminescence performance.

[0011] Technical effects of the present invention:

[0012] (1) The antimony-chromium co-doping of the present invention improves the stability of the material by controlling lattice distortion, passivating defects, optimizing the local coordination environment, and adjusting the band structure. 3+ The lone pair electron effect reduces lattice stress, Cr 3+ Enhancing crystal rigidity reduces the impact of light, temperature, and humidity on the material. In addition, defect passivation reduces environmental sensitivity, and grain optimization reduces surface defects, making the material more stable under light, heat, and humidity conditions.

[0013] (2) This invention uses Sb doping 3+ Change Cr 3+ The crystal field environment makes Cr, which is normally difficult to luminescent in 0D halide perovskites, more luminescent.3+ Transition metals possess excellent near-infrared luminescence, and the material prepared by this invention can be excited by green light to emit near-infrared light.

[0014] (3) By improving the preparation process, the two-step method can further improve the near-infrared luminescence intensity of the material.

[0015] (4) The present invention adopts a simple solid-phase method and the experimental procedure is simple. It is a simple and low-cost method for synthesizing antimony-chromium co-doped halide perovskite. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the crystal structure of the target sample prepared in Example 3.

[0017] Figure 2 This is a schematic diagram of the crystal structure of the target sample prepared in Comparative Example 1.

[0018] Figure 3 This is a schematic diagram of the crystal structure of the target sample prepared in Comparative Example 2.

[0019] Figure 4 The image shows the XRD pattern of the target sample prepared in Example 1.

[0020] Figure 5 The XRD pattern of the target sample prepared in Example 2 is shown.

[0021] Figure 6 The image shows the XRD pattern of the target sample prepared in Example 3.

[0022] Figure 7 The XRD pattern of the target sample prepared in Example 4 is shown.

[0023] Figure 8 The PL spectra of the target samples prepared in Examples 1 to 4 and Comparative Examples 1 to 2 are compared. Detailed Implementation

[0024] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited to the content described.

[0025] Example 1

[0026] Preparation of an antimony-chromium co-doped halide perovskite (one-step method). The general chemical formula of the antimony-chromium co-doped halide perovskite prepared in this embodiment is: Cs3Bi 0.9 Sb 0.05 Cr 0.05 Cl6, the specific preparation method is as follows:

[0027] Weigh the raw materials CsCl, BiCl3, SbCl3, and CrCl3 according to the stoichiometric ratio shown in the general chemical formula. Grind the raw materials thoroughly for 20 minutes. After grinding, sinter at 350℃ for 2 hours to obtain the target sample Cs3Bi. 0.9 Sb 0.05 Cr 0.05 Cl6.

[0028] The target sample Cs3Bi prepared in this embodiment is 0.8 Sb 0.15 Cr 0.05 The XRD pattern of Cl6 is as follows Figure 4 As shown, from Figure 4 The correspondence between the XRD peaks obtained from the sample and the PDF card demonstrates good phase purity.

[0029] Example 2

[0030] Preparation of an antimony-chromium co-doped halide perovskite (one-step method). The general chemical formula of the antimony-chromium co-doped halide perovskite prepared in this embodiment is: Cs3Bi 0.8 Sb 0.15 Cr 0.05 Cl6, the specific preparation method is as follows:

[0031] Weigh the raw materials CsCl, BiCl3, SbCl3, and CrCl3 according to the stoichiometric ratio shown in the general chemical formula. Grind the raw materials thoroughly for 20 minutes. After grinding, sinter at 350℃ for 2 hours to obtain the target sample Cs3Bi. 0.8 Sb 0.15 Cr 0.05 Cl6.

[0032] The target sample Cs3Bi prepared in this embodiment is 0.8 Sb 0.15 Cr 0.05 The XRD pattern of Cl6 is as follows Figure 5 As shown, from Figure 5 The correspondence between the XRD peaks obtained from the sample and the PDF card demonstrates good phase purity.

[0033] Example 3

[0034] Preparation of an antimony-chromium co-doped halide perovskite (two-step method). The general chemical formula of the antimony-chromium co-doped halide perovskite prepared in this embodiment is: Cs3Bi 0.9 Sb 0.05 Cr 0.05 Cl6, the specific preparation method is as follows:

[0035] Weigh the raw materials CsCl, BiCl3, SbCl3, and CrCl3 according to the stoichiometric ratio shown in the general chemical formula; grind CsCl, BiCl3, and SbCl3 thoroughly for 20 minutes, then sinter at 350℃ for 2 hours; after sintering, add CrCl3 and grind thoroughly to obtain the target sample Cs3Bi 0.9 Sb 0.05 Cr 0.05 Cl6.

[0036] The target sample Cs3Bi prepared in this embodiment is 0.8 Sb 0.15 Cr 0.05 A schematic diagram of the crystal structure of Cl6 is shown below. Figure 1 As shown, Figure 1 This shows the matrix Cs3BiCl6 with Sb doping 3+ Based on this, Cr was doped using a two-step method. 3+ Required defect formation energy and Cr 3+ The grid position that one tends to occupy.

[0037] The target sample Cs3Bi prepared in this embodiment is 0.9 Sb 0.05 Cr 0.05 The XRD pattern of Cl6 is as follows Figure 6 As shown, from Figure 6 The correspondence between the XRD peaks obtained from the sample and the PDF card demonstrates good phase purity.

[0038] Example 4

[0039] Preparation of an antimony-chromium co-doped halide perovskite (two-step method). The general chemical formula of the antimony-chromium co-doped halide perovskite prepared in this embodiment is: Cs3Bi 0.8 Sb 0.15 Cr 0.05 Cl6, the specific preparation method is as follows:

[0040] Weigh the raw materials CsCl, BiCl3, SbCl3, and CrCl3 according to the stoichiometric ratio shown in the general chemical formula; grind CsCl, BiCl3, and SbCl3 thoroughly for 20 minutes, then sinter at 350℃ for 2 hours; after sintering, add CrCl3 and grind thoroughly to obtain the target sample Cs3Bi 0.8 Sb 0.15 Cr 0.05 Cl6.

[0041] The target sample Cs3Bi prepared in this embodiment is 0.9 Sb 0.05 Cr 0.05 The XRD pattern of Cl6 is as follows Figure 7As shown, from Figure 7 The correspondence between the XRD peaks obtained from the sample and the PDF card demonstrates good phase purity.

[0042] Comparative Example 1

[0043] Preparation of a chromium-doped halide perovskite: The chromium-doped halide perovskite prepared in this embodiment has the general chemical formula: Cs3Bi 0.95 Cr 0.05 Cl6, the specific preparation method is as follows:

[0044] Weigh the raw materials CsCl, BiCl3, and CrCl3 according to the stoichiometric ratio shown in the general chemical formula. Grind the raw materials thoroughly for 20 minutes. After grinding, sinter at 350℃ for 2 hours to obtain the target sample Cs3Bi. 0.95 Cr 0.05 Cl6.

[0045] The target sample Cs3Bi prepared in this comparative example 0.95 Cr 0.05 A schematic diagram of the crystal structure of Cl6 is shown below. Figure 2 As shown.

[0046] Comparative Example 2

[0047] Preparation of an antimony-doped halide perovskite: The antimony-doped halide perovskite prepared in this embodiment has the general chemical formula: Cs3Bi 0.85 Sb 0.15 Cl6, the specific preparation method is as follows:

[0048] Weigh the raw materials CsCl, BiCl3, and SbCl3 according to the stoichiometric ratio shown in the general chemical formula. Grind the raw materials thoroughly for 20 minutes. After grinding, sinter at 350℃ for 2 hours to obtain the target sample Cs3Bi. 0.95 Cr 0.05 Cl6.

[0049] The target sample Cs3Bi prepared in this comparative example 0.95 Cr 0.05 A schematic diagram of the crystal structure of Cl6 is shown below. Figure 2 As shown.

[0050] Figure 8 The figures show a comparison of the PL spectra of the target samples prepared in Examples 1 to 4 and Comparative Examples 1 to 2. It can be seen from the figures that the target samples prepared in Example 2 and Comparative Example 1 are significantly different from those without Sb. 3+ At that time, Cr 3+ The PL peak is located at 817 nm, and the luminous efficiency is relatively low; it is doped with 15% Sb. 3+ After that, Cr3+ The PL peak was red-shifted to 910 nm, and the luminescence intensity increased by about 100%. Compared with Example 3, the PL intensity of the target sample prepared in Example 3 was increased by up to 300% and the quantum efficiency was increased by 30% compared with the target sample prepared in Example 1. It can be seen from the figure that the target sample obtained by doping only antimony did not emit near-infrared light.

Claims

1. An antimony-chromium co-doped halide perovskite, characterized in that: The general chemical formula of the antimony-chromium co-doped halide perovskite is: Cs3Bi 1-x1-x2 Sb x1 Cr x2 Cl6, where x1 = 0.01~0.2, x2 = 0.01~0.

2.

2. The method for preparing the antimony-chromium co-doped halide perovskite according to claim 1, characterized in that: The raw materials, CsCl, BiCl3, SbCl3 and CrCl3, were weighed according to the stoichiometric ratio in the general chemical formula. CsCl, BiCl3 and SbCl3 were first thoroughly ground and mixed and then sintered. After sintering, CrCl3 was added and thoroughly ground to obtain antimony-chromium co-doped halide perovskite.

3. The method for preparing the antimony-chromium co-doped halide perovskite according to claim 1, characterized in that: The raw materials were weighed according to the stoichiometric ratio in the general chemical formula: CsCl, BiCl3, SbCl3 and CrCl3. After the raw materials were thoroughly ground, they were sintered to obtain antimony-chromium co-doped halide perovskite.

4. The method for preparing antimony-chromium co-doped halide perovskite according to claim 2 or claim 3, characterized in that: The sintering temperature is 300℃~400℃, and the sintering time is 1.5~2 hours.

5. The application of the antimony-chromium co-doped halide perovskite as described in claim 1 in infrared detection and imaging, optical communication and encryption, or infrared LEDs and lasers.

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