Antimony-chromium co-doped halide perovskite and preparation method and application thereof

Abstract

The invention discloses antimony-chromium co-doped halide perovskite as well as a preparation method and application thereof, and belongs to the technical field of photoelectric functional materials. The chemical general formula of the antimony-chromium co-doped halide perovskite is Cs3Bi1-x1-x2Sbx1Crx2Cl6, and the preparation method of the antimony-chromium co-doped halide perovskite comprises the following steps: weighing raw materials including CsCl, BiCl3, SbCl3 and CrCl3 according to the chemical general formula, firstly, fully grinding and mixing CsCl, BiCl3 and SbCl3 and then sintering, after sintering is finished, adding CrCl3 and fully grinding, and then adding the CrCl3 and fully grinding to obtain the antimony-chromium co-doped halide perovskite with the chemical general formula of Cs3Bi1-x1-x2Sbx1Crx2Cl6 and the antimony-chromium co-doped halide perovskite with the chemical general formula of Cs3Bi1-x1-x2Sbx1Crx2Cl6. The antimony-chromium co-doped halide perovskite can also be obtained by grinding all the raw materials together and then sintering the ground raw materials. The halide perovskite disclosed by the invention has excellent near-infrared luminescence performance.

Description

Technical Field

[0001] The invention relates to an antimony-chromium co-doped halide perovskite and a preparation method and application thereof, belonging to the technical field of photoelectric functional materials. Background Art

[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 important applications in night vision, medical imaging, information security, and other fields. However, traditional near-infrared luminescent materials (such as rare earth ion-doped materials) often suffer from low luminous efficiency, difficult synthesis, and high cost.

[0003] Transition metal ion Cr 3+ Due to its dd electron transition characteristics, it has become an important choice for achieving near-infrared luminescence. However, directly doping Cr into low-dimensional halide perovskites (such as Cs3BiCl6) 3+ Will form a weak field luminescence center with low luminescence intensity. Therefore, how to optimize Cr 3+ The near-infrared luminescence efficiency in the Cs3BiCl6 system has become a key issue in current research.

[0004] In existing technologies, achieving co-doping of two metal ions faces multiple challenges, including: differences in the solubility of different ions can easily lead to phase separation, affecting material uniformity; difficulties in energy level matching can reduce energy transfer efficiency and induce non-radiative recombination; the complexity of regulating the valence state of the doped ions affects luminescence performance; the difficulty in determining the optimal doping ratio, as excessively high concentrations can easily induce quenching effects; and the need for precise control of reaction conditions during the preparation process to ensure the stability of the material structure and optical properties. These issues have limited the further application of co-doping systems in the field of near-infrared luminescence. Summary of the Invention

[0005] In order to solve the problem of low near-infrared luminescence efficiency of existing halide perovskites, one of the purposes of the present invention is to provide an antimony-chromium co-doped halide perovskite, the 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.

[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: CsCl, BiCl3, SbCl3 and CrCl3 according to the stoichiometric ratio in the chemical formula, first grind CsCl, BiCl3 and SbCl3 thoroughly and mix them, then sinter them, and then add CrCl3 after sintering to obtain antimony-chromium co-doped halide perovskite. This method is a two-step method.

[0007] The present invention also provides another method for preparing antimony-chromium co-doped halide perovskite: weighing raw materials: CsCl, BiCl3, SbCl3 and CrCl3 according to the stoichiometric ratio in the chemical formula, fully grinding the raw materials and then sintering to obtain antimony-chromium co-doped halide perovskite. This method is a one-step method.

[0008] Preferably, the sintering temperature is 300° C. to 400° C., and the sintering time is 1.5 to 2 hours.

[0009] The antimony-chromium co-doped halide perovskite of the present invention is used in infrared detection and imaging, optical communication and encryption, biological labeling and phototherapy, or infrared LEDs and lasers.

[0010] The present invention adopts Cs3BiCl6 as the matrix and dopes 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 the lattice site that is conducive to luminescence and optimize the luminescence center; adopt the two-step doping method, first doping Sb 3+ Cr doping 3 + , which can further improve the 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 regulating lattice distortion, passivating defects, optimizing local coordination environment and adjusting the band structure. 3+ The lone pair electron effect of Cr reduces the lattice stress. 3+ Enhance crystal rigidity and jointly reduce the effects 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) The present invention is doped with Sb 3+ Change Cr 3+ The crystal field environment makes it difficult for Cr to emit light in 0D halide perovskites.3+ Transition metals have good near-infrared luminescence, and the material prepared by the present invention can be excited by green light to emit near-infrared luminescence.

[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 with a simple experimental process. This is a simple and low-cost method for synthesizing antimony-chromium co-doped halide perovskite. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of the crystal structure of the target sample prepared in Example 3.

[0017] Figure 2 Schematic diagram of the crystal structure of the target sample prepared in Comparative Example 1.

[0018] Figure 3 Schematic diagram of the crystal structure of the target sample prepared in Comparative Example 2.

[0019] Figure 4 This is the XRD pattern of the target sample prepared in Example 1.

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

[0021] Figure 6 This is the XRD pattern of the target sample prepared in Example 3.

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

[0023] Figure 8 PL spectra comparison of the target samples prepared in Examples 1 to 4 and Comparative Examples 1 to 2. DETAILED DESCRIPTION

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

[0025] Example 1

[0026] Preparation of an antimony-chromium co-doped halide perovskite (one-step method). The 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] The raw materials: CsCl, BiCl3, SbCl3 and CrCl3 were weighed according to the stoichiometric ratio shown in the chemical formula. The raw materials were fully ground for 20 minutes and sintered 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 example 0.8 Sb 0.15 Cr 0.05 The XRD pattern of Cl6 is as follows Figure 4 As shown, from Figure 4 It can be seen that the XRD peaks obtained from the sample correspond to the PDF card, which proves the good phase purity.

[0029] Example 2

[0030] Preparation of an antimony-chromium co-doped halide perovskite (one-step method). The 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] The raw materials: CsCl, BiCl3, SbCl3 and CrCl3 were weighed according to the stoichiometric ratio shown in the chemical formula. The raw materials were fully ground for 20 minutes and sintered 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 example 0.8 Sb 0.15 Cr 0.05 The XRD pattern of Cl6 is as follows Figure 5 As shown, from Figure 5 It can be seen that the XRD peaks obtained from the sample correspond to the PDF card, which proves the good phase purity.

[0033] Example 3

[0034] Preparation of an antimony-chromium co-doped halide perovskite (two-step method). The 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 according to the stoichiometric ratio shown in the chemical formula: CsCl, BiCl3, SbCl3 and CrCl3; grind CsCl, BiCl3 and SbCl3 thoroughly for 20 minutes and 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 example 0.8 Sb 0.15 Cr 0.05 The crystal structure diagram of Cl6 is as follows Figure 1 As shown, Figure 1 It shows that the matrix Cs3BiCl6 is doped with Sb 3+ Based on the two-step method, Cr is doped 3+ The required defect formation energy and Cr 3+ The preferred space to occupy.

[0037] The target sample Cs3Bi prepared in this example 0.9 Sb 0.05 Cr 0.05 The XRD pattern of Cl6 is as follows Figure 6 As shown, from Figure 6 It can be seen that the XRD peaks obtained from the sample correspond to the PDF card, which proves the good phase purity.

[0038] Example 4

[0039] Preparation of an antimony-chromium co-doped halide perovskite (two-step method). The 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 according to the stoichiometric ratio shown in the chemical formula: CsCl, BiCl3, SbCl3 and CrCl3; grind CsCl, BiCl3 and SbCl3 thoroughly for 20 minutes and 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 example 0.9 Sb 0.05 Cr 0.05 The XRD pattern of Cl6 is as follows Figure 7As shown, from Figure 7 It can be seen that the XRD peaks obtained from the sample correspond to the PDF card, which proves the good phase purity.

[0042] Comparative Example 1

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

[0044] The raw materials: CsCl, BiCl3 and CrCl3 were weighed according to the stoichiometric ratio shown in the chemical formula. The raw materials were fully ground for 20 minutes and sintered 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 The crystal structure diagram of Cl6 is as follows Figure 2 shown.

[0046] Comparative Example 2

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

[0048] The raw materials: CsCl, BiCl3 and SbCl3 were weighed according to the stoichiometric ratio shown in the chemical formula. The raw materials were fully ground for 20 minutes and sintered 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 The crystal structure diagram of Cl6 is as follows Figure 2 shown.

[0050] Figure 8 The PL spectra of the target samples prepared in Examples 1 to 4 and Comparative Examples 1 to 2 are compared. It can be seen from the figure that the target samples prepared in Example 2 and Comparative Example 1 have a higher PL spectrum than those without Sb doping. 3+ When Cr 3+ The PL peak is located at 817nm, and the luminous efficiency is low; doped with 15% Sb 3+ After that, Cr3+ The PL peak red-shifts to 910 nm, and the luminescence intensity increases by about 100%. Compared with Example 1 and Example 3, the PL intensity of the target sample prepared in Example 3 is increased by up to 300% compared with the target sample prepared in Example 1, and the quantum efficiency is increased by 30%. It can be seen from the figure that the target sample obtained when only antimony is doped has no near-infrared luminescence.

Claims

1. An antimony-chromium co-doped halide perovskite, characterized in that: The 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 are weighed according to the stoichiometric ratio in the chemical formula. CsCl, BiCl3 and SbCl3 are first fully ground and mixed and then sintered. After the sintering is completed, CrCl3 is added and fully 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: Raw materials: CsCl, BiCl3, SbCl3 and CrCl3 are weighed according to the stoichiometric ratio in the general chemical formula, and the raw materials are fully ground and then sintered to obtain antimony-chromium co-doped halide perovskite.

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

5. Application of the antimony-chromium co-doped halide perovskite according to claim 1 in infrared detection and imaging, optical communication and encryption, bio-labeling and phototherapy, or infrared LEDs and lasers.

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