Molybdenum-doped all-inorganic hole-ordered double perovskites, their preparation methods and applications

Abstract

This invention relates to the field of luminescent materials technology, and more specifically, to molybdenum-doped fully inorganic hole-ordered double perovskites, their preparation methods, and applications. The first aspect of this invention provides three types of molybdenum-doped fully inorganic hole-ordered double perovskites: tetravalent molybdenum-doped, pentavalent molybdenum-doped, and co-doped with tetravalent and pentavalent molybdenum, with the chemical formulas Cs₂Sn₂, respectively. 1‑x Cl6:xMo 4+ Cs2Sn 1‑y (O y Cl 6‑y ):yMo 5+ and Cs2Sn 1‑a‑b (O b Cl 6‑b ):aMo 4+ ,bMo 5+ The second aspect of this invention provides methods for preparing three types of molybdenum-doped fully inorganic hole-ordered double perovskites: tetravalent molybdenum-doped, pentavalent molybdenum-doped, and co-doped with tetravalent and pentavalent molybdenum. The third aspect provides applications of these three types of molybdenum-doped fully inorganic hole-ordered double perovskites in product testing, anti-counterfeiting, safety monitoring, non-destructive analysis, light-emitting LEDs, solar cells, temperature detectors, multispectral imaging, ultra-wideband light sources, or broadband photodetectors. The fourth aspect provides an optoelectronic device in which the luminescent material is this molybdenum-doped fully inorganic hole-ordered double perovskite.

Description

Technical Field

[0001] This invention relates to the field of luminescent materials technology, and more specifically, to molybdenum-doped fully inorganic hole-ordered double perovskite, its preparation method, and its application. Background Technology

[0002] All-inorganic hole-ordered double perovskites (A₂BX₆), where A is a monovalent cation, B is a tetravalent metal ion, and X is an anion, have attracted widespread attention due to their unique electronic structure and excellent stability. By doping the double perovskite matrix with transition metal ions, their luminescence properties can be effectively modulated, expanding their application range.

[0003] In recent years, molybdenum has been recognized as an important doping activator, exhibiting unique luminescent properties in various luminescent materials. For example, some literature reports that a molybdenum-doped all-inorganic hole-ordered double perovskite near-infrared phosphor exhibits advantages such as high stability and high quantum efficiency. Chem.mater. 2024, 36(2) , 901-910 / Chem.mater. 2024, 36(9) ,4561-4570 / Laser Photonics Rev. 2025, 2500311 / ACSmaterials Lett. 2025, 7 , 2190-2198 / Chem. Eng. J. 517(2025), 164543 / Laser Photonics Rev. 2025, e00755). However, existing publicly disclosed molybdenum-doped all-inorganic hole-ordered double perovskites typically exhibit emission in a single-band near-infrared region. Summary of the Invention

[0004] The present invention aims to overcome at least one of the defects of the prior art mentioned above, and provides molybdenum-doped fully inorganic hole-ordered double perovskite, its preparation method and application, so as to solve the problem of single emission spectrum band.

[0005] The primary objective of this invention is to propose a tetravalent molybdenum-doped, fully inorganic, hole-ordered double perovskite with the chemical formula Cs₂Sn. 1-x Cl6:xMo 4+ Where 0.1%≤x≤5%.

[0006] The tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite of this invention uses Cs₂SnCl₆ as a matrix, where x is the dopant ion Mo. 4+ The molar percentage relative to the matrix ion Sn. Tests show that the tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite of this invention has a Cs₂SnCl₆ type crystal structure, in which a portion of Sn... 4+ Site or by Mo 4+Ions occupy the phosphor, forming luminescent centers. X-ray diffraction (XRD) patterns show that its main phase matches the standard card (PDF#75-0376) for Cs₂SnCl₆. Absorption spectroscopy analysis indicates the presence of [MoCl₆] in the phosphor. 2- The associated charge-transfer (CT) transition characteristic absorption peaks confirmed that molybdenum ions exist in the +4 valence state. Scanning electron microscopy (SEM) observation showed that the phosphor typically exhibits a polygonal micron-sized particle morphology with uneven particle size, relatively smooth surface, and some particles showing good crystal properties.

[0007] Furthermore, the fluorescence emission spectra of the tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite are 700-800 nm and 1200-1600 nm.

[0008] Furthermore, the absorption spectrum of the tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite is 250-450 nm.

[0009] The second objective of this invention is to provide a method for preparing the tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite, comprising: mixing CsCl, SnCl2 and MoCl5, adding concentrated hydrochloric acid and mixing thoroughly, and then heating, cooling, separating, washing and drying to obtain the tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite.

[0010] The third objective of this invention is to propose the application of the aforementioned tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite in the fields of product testing, anti-counterfeiting, safety monitoring, or non-destructive analysis.

[0011] The fourth objective of this invention is to propose a pentavalent molybdenum-doped, fully inorganic, hole-ordered double perovskite with the chemical formula Cs₂Sn. 1-y (O y Cl 6-y ):yMo 5+ Where 0.1%≤y≤5%.

[0012] The pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite of this invention uses Cs₂Sn(OCl)₆ as the matrix, where y is the dopant ion Mo. 5+ Relative to the molar percentage content of the matrix ion Sn. Tests show that the pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite of this invention has the same crystal structure as Cs₂SnCl₆, wherein a portion of Sn... 4+ Site or by Mo 5+ Ions occupy the space, thus forming luminescent centers. Absorption spectroscopy analysis shows that [MoO] exists in this pentavalent molybdenum-doped, fully inorganic hole-ordered double perovskite. x Cl 6-x ] 2-The relevant characteristic absorption peaks, such as the charge migration (CT) transition absorption peak and the dd transition absorption peak, confirmed that the molybdenum ion exists in the +5 valence state.

[0013] Furthermore, the fluorescence emission spectra of the pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite are 450-750 nm and 800-1200 nm.

[0014] Furthermore, the absorption spectrum of the pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite is 250-370 nm.

[0015] The fifth objective of this invention is to provide a method for preparing the pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite, comprising: mixing CsCl, SnCl4·4H2O and MoCl5, adding concentrated hydrochloric acid and mixing well, and then heating, cooling, separating, washing and drying to obtain the pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite.

[0016] The sixth objective of this invention is to propose the application of the aforementioned pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite in the preparation of light-emitting LEDs, anti-counterfeiting devices, solar cells, or temperature detectors.

[0017] The seventh objective of this invention is to propose a co-doped, tetravalent and pentavalent molybdenum, fully inorganic hole-ordered double perovskite with the chemical formula Cs₂Sn. 1-a-b (O b Cl 6-b ):aMo 4+ ,bMo 5+ Where 0.1% ≤ (a+b) ≤ 5%, and .

[0018] The tetravalent and pentavalent molybdenum co-doped fully inorganic hole-ordered double perovskite of the present invention uses Cs₂Sn(OCl)₆ as the matrix, wherein a is the dopant ion Mo. 4+ b represents the molar percentage of the dopant ion Mo relative to the matrix ion Sn. 5+ Relative to the molar percentage content of the matrix ion Sn. Tests show that the tetravalent and pentavalent molybdenum co-doped fully inorganic hole-ordered double perovskite of this invention has the same crystal structure as Cs₂SnCl₆, wherein a portion of Sn... 4+ The site is Mo 4+ and Mo 5+ Ions occupy the luminescent centers, and absorption spectroscopy analysis shows that this co-doped tetravalent and pentavalent molybdenum fully inorganic hole-ordered double perovskite exists in [MoOCl5]. 2- and [MoCl6] 2- The relevant characteristic absorption peaks confirmed that molybdenum ions exist in two valence states: +4 and +5.

[0019] Furthermore, the fluorescence emission spectrum of the tetravalent and pentavalent molybdenum co-doped fully inorganic hole-ordered double perovskite covers the range of 500-1600 nm.

[0020] Furthermore, the absorption spectrum of the tetravalent and pentavalent molybdenum co-doped fully inorganic hole-ordered double perovskite is 250-450 nm.

[0021] The eighth objective of this invention is to provide a method for preparing the tetravalent and pentavalent molybdenum co-doped fully inorganic hole-ordered double perovskite, comprising: mixing CsCl, SnCl2, SnCl4·4H2O and MoCl5, adding concentrated hydrochloric acid and mixing well, and then heating, cooling, separating, washing and drying to obtain the tetravalent and pentavalent molybdenum co-doped fully inorganic hole-ordered double perovskite.

[0022] The ninth objective of this invention is to propose the application of the aforementioned tetravalent and pentavalent molybdenum co-doped fully inorganic hole-ordered double perovskite in the fields of multispectral imaging, high-end anti-counterfeiting, ultra-wideband light sources, or broadband photodetectors.

[0023] The tenth objective of this invention is to provide an optoelectronic device in which the luminescent material is a tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite, or a pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite, or a co-doped fully inorganic hole-ordered double perovskite with both tetravalent and pentavalent molybdenum.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows: 1) The tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite proposed in this invention can simultaneously generate dual emission in the near-infrared I region (700-800nm) and the near-infrared II region (1200-160nm) under single-wavelength excitation, which is different from the previously reported Mo 4+The doping phenomenon is significantly different from the near-infrared single emission phenomenon, and has potential application value in product testing, anti-counterfeiting, security monitoring, or non-destructive analysis; 2) This invention successfully prepared pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite for the first time, expanding the research system of this type of material. Under single-wavelength excitation, the pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite can simultaneously produce double emission in the visible light region (about 575nm) and the near-infrared light region (about 950nm), and has a wide total spectral coverage with a full width at half maximum (FWHM) of up to 312nm. It has potential applications in light-emitting LEDs, anti-counterfeiting, and solar energy. 3) The tetravalent and pentavalent molybdenum co-doped fully inorganic hole-ordered double perovskite proposed in this invention exhibits ultra-wideband luminescence characteristics from visible light to near-infrared (500-1600nm) under single-wavelength excitation. Based on its unique luminescence performance, the tetravalent and pentavalent molybdenum co-doped fully inorganic hole-ordered double perovskite has potential application value in multispectral imaging, high-end anti-counterfeiting, ultra-wideband light source or broadband photodetector; 4) The hydrothermal synthesis method proposed in this invention is relatively simple, easy to operate and scale up. Attached Figure Description

[0025] Figure 1 The tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite phosphors (Cs2Sn) with different doping concentrations prepared in Example 1 1-x Cl6:xMo 4+ X-ray diffraction (XRD) pattern of x ≤ 1.4% (0.4% ≤ x ≤ 1.4%).

[0026] Figure 2 The tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite phosphor (Cs2Sn) prepared in Example 2 0.996 Cl6: 0.4%Mo 4+ The absorption spectrum of ).

[0027] Figure 3 The tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite phosphor (Cs2Sn) prepared in Example 3 0.99 Cl6: 1.0%Mo 4+ Scanning electron microscope (SEM) image.

[0028] Figure 4 The tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite phosphor (Cs2Sn) prepared in Example 4 0.996 Cl6: 0.4%Mo 4+ Fluorescence emission spectrum under 310 nm excitation.

[0029] Figure 5 The absorption spectrum of the molybdenum-doped all-inorganic hole-ordered double perovskite phosphor prepared in Comparative Example 1 is shown.

[0030] Figure 6 The pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite phosphors [Cs2Sn] with different doping concentrations prepared in Example 5 1-y (O y Cl 6-y ):yMo 5+ X-ray diffraction (XRD) pattern of 0.4% ≤ y ≤ 1.4%.

[0031] Figure 7 The pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite phosphor [Cs2Sn] prepared in Example 6 0.996 (O 0.004 Cl 5.996 ):0.4%Mo 5+ The absorption spectrum of ].

[0032] Figure 8 The pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite phosphor [Cs2Sn] prepared in Example 7 0.99 (O 0.01 Cl 5.99 ):1.0%Mo 5+ Scanning electron microscope (SEM) image.

[0033] Figure 9 The pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite phosphor [Cs2Sn] prepared in Example 8 0.996 (O 0.004 Cl 5.996 ):0.4%Mo 5+ Fluorescence emission spectrum under 310 nm excitation.

[0034] Figure 10 The absorption spectrum of the molybdenum-doped all-inorganic hole-ordered double perovskite phosphor prepared for Comparative Example 2 is shown.

[0035] Figure 11 The tetravalent and pentavalent molybdenum co-doped fully inorganic hole-ordered double perovskite phosphor (Cs2Sn) prepared in Example 9 0.996 (O 0.002 Cl 5.998 ):0.2%Mo 4+ 0.2%Mo 5+ X-ray diffraction (XRD) pattern of ).

[0036] Figure 12 The tetravalent and pentavalent molybdenum co-doped fully inorganic hole-ordered double perovskite phosphor [Cs2Sn] prepared in Example 10 0.996 (O 0.002 Cl 5.998 ):0.2%Mo 4+ 0.2%Mo5+ The absorption spectrum of ].

[0037] Figure 13 The tetravalent and pentavalent molybdenum co-doped fully inorganic hole-ordered double perovskite phosphor [Cs2Sn] prepared in Example 11 0.99 (O 0.002 Cl 5.998 ):0.8%Mo 4+ 0.2%Mo 5+ Scanning electron microscope (SEM) image.

[0038] Figure 14 The fluorescence emission spectra of the four tetravalent and pentavalent molybdenum co-doped fully inorganic hole-ordered double perovskite phosphors prepared in Example 12 are shown.

[0039] Figure 15 The emission spectrum of the molybdenum-doped all-inorganic hole-ordered double perovskite phosphor prepared in Comparative Example 3 is shown.

[0040] Figure 16 The absorption spectrum of the molybdenum-doped all-inorganic hole-ordered double perovskite phosphor prepared in Comparative Example 4 is shown. Detailed Implementation

[0041] The primary objective of this invention is to propose a tetravalent molybdenum-doped, fully inorganic, hole-ordered double perovskite with the chemical formula Cs₂Sn. 1-x Cl6:xMo 4+ Where 0.1%≤x≤5%.

[0042] Ideally, 0.4% ≤ x ≤ 1.4%.

[0043] The second objective of this invention is to provide a method for preparing the aforementioned tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite, comprising: placing CsCl, SnCl2, and MoCl5 in a polytetrafluoroethylene liner, adding concentrated hydrochloric acid as a solvent and reaction medium for mixing; sealing the polytetrafluoroethylene liner containing the mixture in a hydrothermal reactor, then heating the hydrothermal reactor to a predetermined temperature and holding it at that temperature for a period of time to carry out the hydrothermal reaction; after the reaction is completed, slowly cooling the reactor to room temperature; separating the generated crystalline product from the mother liquor, washing it with a small amount of ethanol, and finally drying it in an oven at a specific temperature to obtain the aforementioned tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite, specifically, existing in the form of phosphor.

[0044] In practice, the molar ratio of CsCl to SnCl2 is controlled at approximately 2:1, while the molar doping amount of MoCl5 relative to SnCl2 can be adjusted within the range of 0.1% to 5%, preferably 0.4% to 1.4%, such as 0.4%, 1.0%, 1.4%, etc.

[0045] In practice, the concentration of concentrated hydrochloric acid is usually the same as that of commercially available concentrated hydrochloric acid, for example, 36%-38% (mass percentage). Furthermore, the amount of concentrated hydrochloric acid used also affects the morphology and crystallinity of the reaction product. Preferably, the amount of concentrated hydrochloric acid used relative to 1 mmol of SnCl2 can be between 1 mL and 10 mL. For example, the amount of concentrated hydrochloric acid used can be 2 mL, 3 mL, 5 mL, 6 mL, 8 mL, or 10 mL.

[0046] In practice, the heating temperature range of the hydrothermal reaction is 140°C. o C to 230 o C, for example, 140°C, 160°C o C, 180 o C, 200 o C. 230℃. In addition, the heat preservation time ranges from 5 hours to 30 hours, for example, 5 hours, 10 hours, 12 hours, 15 hours, 20 hours, 25 hours, and 30 hours.

[0047] In practice, the heating rate of the hydrothermal reaction is controlled at 1. o C / minute to 10 o C / minute, for example, about 3 o C / minute, 5 o C / minute, 10 o C / minute.

[0048] In practice, the cooling rate is 10–30°C. o C / hour, for example, the cooling rate can be adjusted to 10 °C / hour. o C / hour, 15 o C / hour, 20 o C / hour, 25 o C / hour, 30 o C / hour.

[0049] In practice, the drying temperature is 40℃-80℃, for example, it can be set to 40℃, 50℃, 60℃, 70℃, 80℃, etc., to ensure that the product is completely dried.

[0050] The purpose of ethanol washing is to remove impurities and residual reaction liquor adsorbed on the surface of the product. The number of washing cycles is usually 2 to 5.

[0051] A significant feature of the tetravalent molybdenum-doped all-inorganic hole-ordered double perovskite phosphor is its unique luminescence properties. Specifically, under ultraviolet to near-ultraviolet light excitation with wavelengths of 250-450 nm, the phosphor can simultaneously produce bimodal emission in both the near-infrared I and near-infrared II regions. Specifically, the center of its near-infrared I emission peak is located at approximately 718 nm, with a spectral coverage of approximately 700-800 nm; its near-infrared emission peak is located at approximately 1350 nm, with a spectral coverage of approximately 1200-1600 nm.

[0052] Based on this, the third objective of the present invention is to propose the application of the aforementioned tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite in the fields of product testing, anti-counterfeiting, safety monitoring, or non-destructive analysis.

[0053] When used for product testing, the tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite emits near-infrared I (700nm-800nm) and near-infrared II (1200nm-1600nm) dual-band emission under specific excitation. This emission can penetrate product packaging or surface materials (such as plastics, paper, and coatings), enabling high-sensitivity, high-resolution imaging detection of internal structures, defects (such as cracks, bubbles, and foreign matter), or component distribution. It is particularly suitable for industrial and quality inspection fields such as internal packaging integrity inspection of electronic components, interface analysis of multilayer composite materials, and screening of foreign matter inside food and drug packaging.

[0054] When used as an anti-counterfeiting material, the dual-emission characteristics of the tetravalent molybdenum-doped, fully inorganic, hole-ordered double perovskite under specific excitation can serve as a unique anti-counterfeiting identifier. Utilizing its simultaneously emitted near-infrared I and near-infrared II fluorescence signals, which possess distinct wavelength characteristics and are difficult to imitate, a high-level dual-channel or ratiometric anti-counterfeiting identifier can be constructed. This identifier is invisible under conventional light sources and requires specific excitation light sources and dual-band near-infrared detection equipment for reading and verification, significantly improving the security and reliability of the anti-counterfeiting label. It is suitable for anti-counterfeiting of important documents, branded goods, high-end packaging, and currency securities.

[0055] When used for safety monitoring, the strong near-infrared II penetration capability of the tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite enables it to transmit signals through smoke, fog, turbid liquids, or non-metallic obstacles of a certain thickness. Utilizing this characteristic, it can be made into markers or sensing probes for location identification in fire smoke environments, long-range tracing and monitoring of key targets in underwater or turbid waters, and penetrating sensing of the internal state of specific confined spaces or pipelines, thus enhancing safety monitoring capabilities in complex environments.

[0056] When used for non-destructive analysis, the deep penetration characteristics and dual-band emission of the tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite, combined with its fluorescence response changes that may occur in response to specific environmental factors (such as temperature, pressure, and specific substances), can be used for non-contact, non-destructive analysis of the composition and state of fragile or precious samples. For example, it can be applied to the non-destructive assessment of the internal quality (maturity, lesions, moisture) of agricultural products (such as fruits and grains), the analysis of the internal structure and restoration materials of cultural relics, or the in-situ monitoring of the aging process of industrial materials (such as coatings and films).

[0057] The fourth objective of this invention is to propose a pentavalent molybdenum-doped, fully inorganic, hole-ordered double perovskite with the chemical formula Cs₂Sn. 1-y (O y Cl 6-y ):yMo 5+ Where 0.1%≤y≤5%.

[0058] Ideally, 0.4% ≤ y ≤ 1.4%.

[0059] The pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite has a Cs2Sn(OCl)6 type crystal structure, in which some Sn 4+ Site or by Mo 5+ Ions occupy the luminescent sites, forming luminescent centers. X-ray diffraction (XRD) patterns show that its main phase matches the standard card (PDF#75-0376) for Cs₂SnCl₆. Absorption spectroscopy analysis indicates the presence of [MoO₂] in this pentavalent molybdenum-doped, fully inorganic, hole-ordered double perovskite. x Cl 6-x ] 2- The relevant characteristic absorption peaks, such as charge migration (CT) transition absorption peaks and dd transition absorption peaks, confirmed that molybdenum ions exist in the +5 valence state. Scanning electron microscopy (SEM) observation showed that the phosphor typically exhibits a polygonal micron-sized particle morphology, with potentially non-uniform particle size, relatively smooth surfaces, and some particles displaying good crystal properties.

[0060] The fifth objective of this invention is to provide a method for preparing the pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite, comprising: placing cesium chloride (CsCl), tin tetrahydrate (SnCl4·4H2O), and molybdenum pentachloride (MoCl5) as raw materials in a polytetrafluoroethylene liner, adding concentrated hydrochloric acid as a solvent and reaction medium for mixing; sealing the polytetrafluoroethylene liner containing the mixture in a hydrothermal reactor, then heating the hydrothermal reactor to a predetermined temperature and holding it at that temperature for a period of time to carry out the hydrothermal reaction; after the reaction is completed, slowly cooling the reactor to room temperature; separating the generated crystalline product from the mother liquor, washing it several times with a small amount of ethanol, and finally drying it in an oven at a specific temperature to obtain the pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite, specifically, existing in the form of phosphor.

[0061] In practice, the molar ratio of CsCl to SnCl4·4H2O is controlled at approximately 2:1, while the molar doping amount of MoCl5 relative to SnCl4·4H2O can be adjusted within the range of 0.1% to 5%, preferably 0.4% to 1.4%, specifically, for example, 0.4%, 1.0%, and 1.4%.

[0062] In practice, the amount of concentrated hydrochloric acid used can be between 1 mL and 10 mL relative to 1 mmol of SnCl4·4H2O.

[0063] In practice, the heating temperature range of the hydrothermal reaction is 140°C. o C to 230 o C, for example, such as 140°C, 160°C o C, 180 o C, 200 o C. 230℃. In addition, the heat preservation time ranges from 5 hours to 30 hours, and in specific implementation, for example, 5 hours, 10 hours, 12 hours, 15 hours, 20 hours, 25 hours, and 30 hours.

[0064] In practice, the heating rate of the hydrothermal reaction is controlled at 1. o C / minute to 10 o C / minute, for example, about 3 o C / minute, 5 o C / minute, 10 o C / minute.

[0065] In practice, the cooling rate is 10–30°C. o C / hour, for example, the cooling rate can be adjusted to 10 °C / hour. o C / hour, 15 o C / hour, 20 o C / hour, 25 o C / hour, 30o C / hour.

[0066] In practice, the drying temperature is 40℃-80℃, for example, 40℃, 50℃, 60℃, 70℃, 80℃, etc., to ensure that the product is completely dried.

[0067] The purpose of ethanol washing is to remove impurities and residual reaction liquor adsorbed on the surface of the product. The number of washing cycles is usually 2 to 5.

[0068] A significant feature of the pentavalent molybdenum-doped all-inorganic hole-ordered double perovskite phosphor is its unique luminescence properties. Specifically, under ultraviolet to near-ultraviolet light excitation at wavelengths of 250-370 nm, the phosphor can simultaneously emit a broadband spectrum covering both the visible and near-infrared regions. Specifically, its visible light emission peak is centered at approximately 575 nm, with a spectral coverage of approximately 450-750 nm; its near-infrared emission peak is centered at approximately 950 nm, with a spectral coverage of approximately 800-1200 nm. This dual-emission characteristic allows its total spectral half-width (FWHM) to reach, for example, approximately 312 nm.

[0069] Based on this, the sixth objective of this invention is to propose the application of the pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite in the preparation of light-emitting LEDs, anti-counterfeiting devices, solar cells, or temperature detectors.

[0070] When used as a light-emitting LED, the pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite can be combined with an ultraviolet LED chip to achieve the output of a specific spectrum through light color conversion, such as for generating broadband white light or visible and near-infrared light in specific bands.

[0071] When used as an anti-counterfeiting material, the pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite's dual emission characteristics (visible yellow light and invisible near-infrared light) under specific excitation can serve as a unique anti-counterfeiting identifier.

[0072] When used in solar cells, the broadband absorption and near-infrared emission characteristics of the pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite may help improve the spectral response range or energy conversion efficiency of the solar cell.

[0073] When used as a temperature detector, the emission intensity, peak position, or lifetime of the visible and / or near-infrared light of the pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite may change regularly with temperature, thus enabling non-contact temperature sensing.

[0074] The seventh objective of this invention is to propose a co-doped, tetravalent and pentavalent molybdenum, fully inorganic hole-ordered double perovskite with the chemical formula Cs₂Sn. 1-a-b (O b Cl6-b ):aMo 4+ ,bMo 5+ Where 0.1% ≤ (a+b) ≤ 5%, and .

[0075] Preferably, 0.4% ≤ (a+b) ≤ 1.4%.

[0076] The eighth objective of this invention is to provide a method for preparing the co-doped tetravalent and pentavalent molybdenum fully inorganic hole-ordered double perovskite, comprising: placing cesium chloride (CsCl), tin dichloride (SnCl2), tin tetrachloride hydrate (SnCl4·5H2O), and molybdenum pentachloride (MoCl5) as raw materials in a polytetrafluoroethylene liner, adding concentrated hydrochloric acid as a solvent and reaction medium for mixing; sealing the polytetrafluoroethylene liner containing the mixture in a hydrothermal reactor, then heating the hydrothermal reactor to a predetermined temperature and holding it at that temperature for a period of time to carry out the hydrothermal reaction; after the reaction is completed, slowly cooling the reactor to room temperature; separating the generated crystalline product from the mother liquor, washing it with a small amount of ethanol, and finally drying it in an oven at a specific temperature to obtain the co-doped tetravalent and pentavalent molybdenum fully inorganic hole-ordered double perovskite, which exists in the form of phosphor.

[0077] The molar ratio of CsCl, tin raw materials (including SnCl2 and SnCl4·4H2O), and MoCl5 was optimized to obtain a product with the target luminescent properties. Specifically, the molar ratio of CsCl to tin raw materials was controlled at approximately 2:1, while the molar doping amount of MoCl5 relative to tin raw materials could be adjusted within the range of 0.1% to 5%, preferably 0.4% to 1.4%, specifically 0.4%, 1.0%, and 1.4%. Furthermore, the molar ratio of tin dichloride to tin tetrachloride hydrate was controlled at 1:9 to 9:1 to ensure that a final product with the target luminescent properties could be obtained. It should be noted that the above... The specific ratio is determined by the molar ratio of tin dichloride and tin tetrachloride hydrate. In practice, The values ​​can be 2:8, 4:6, 5:5, 6:4, 8:2, etc.

[0078] In practice, the amount of concentrated hydrochloric acid used can be between 1 mL and 10 mL relative to 1 mmol of tin raw material. For example, the amount of concentrated hydrochloric acid used can be 2 mL, 3 mL, 5 mL, 6 mL, 8 mL, or 10 mL.

[0079] In practice, the heating temperature range of the hydrothermal reaction is 140°C. o C to 230 o C, for example, 140℃, 160℃ o C, 180 o C, 200o C. 230℃. In addition, the heat preservation time ranges from 5 hours to 30 hours, for example, 5 hours, 10 hours, 12 hours, 15 hours, 20 hours, 25 hours, and 30 hours.

[0080] In practice, the heating rate of the hydrothermal reaction is controlled at 1. o C / minute to 10 o C / minute, for example, about 3 o C / minute, 5 o C / minute, 10 o C / minute.

[0081] In practice, the cooling rate to room temperature is 10–30%. o C / hour, for example, the cooling rate can be adjusted to 10 °C / hour. o C / hour, 15 o C / hour, 20 o C / hour, 25 o C / hour, 30 o C / hour.

[0082] In specific implementation, the drying temperature is 40℃-80℃. For example, the drying temperature can be set to 40℃, 50℃, 60℃, 70℃, 80℃, etc., to ensure that the product is completely dried.

[0083] A significant characteristic of the co-doped tetravalent and pentavalent molybdenum fully inorganic hole-ordered double perovskite is its unique luminescent properties. Specifically, under ultraviolet to near-ultraviolet light excitation with wavelengths of 250-450 nm, it can emit visible-near-infrared light covering 500-1600 nm. Based on this, the ninth objective of this invention is to propose applications of the co-doped tetravalent and pentavalent molybdenum fully inorganic hole-ordered double perovskite in the fields of multispectral imaging, high-end anti-counterfeiting, ultra-wideband light sources, or broadband photodetectors.

[0084] When used in multispectral imaging, the ultrawideband visible-near-infrared emission (500-1600nm) generated by the tetravalent and pentavalent molybdenum co-doped fully inorganic hole-ordered double perovskite under specific excitation can simultaneously capture high-resolution visible light signals from superficial tissues and penetrating signals from deep tissues in a single imaging session, achieving seamless integration from cellular-level observation to in vivo tumor deep navigation.

[0085] When used in high-end anti-counterfeiting applications, the co-doped tetravalent and pentavalent molybdenum fully inorganic hole-ordered double perovskite, under specific excitation, can synergistically output dynamic color in the visible region and multiple hidden codes in the near-infrared region (such as 718nm / 1350nm dual-channel fingerprints) to construct a human-eye-machine dual-level verification system, significantly improving the non-replicability of anti-counterfeiting labels.

[0086] When used as an ultra-wideband light source, the tetravalent and pentavalent molybdenum co-doped fully inorganic hole-ordered double perovskite can directly cover the entire visible-shortwave infrared band (500-1600nm) under a single near-infrared laser drive, replacing the traditional multi-LED combination scheme and providing a lightweight, low-power lighting core for night vision security and autonomous driving infrared imaging systems.

[0087] When used as a broadband photodetector, the tetravalent and pentavalent molybdenum co-doped fully inorganic hole-ordered double perovskite extends the response boundary of the silicon-based detector from 1100nm to 1600nm through a fluorescence conversion layer, while retaining visible light response capability. This breaks through the material bandgap limitation and realizes full-spectrum sensing from visible light to short-wave infrared with a single device.

[0088] The tenth objective of this invention is to provide an optoelectronic device in which the luminescent material is a tetravalent molybdenum-doped fully inorganic hole-ordered double perovskite, or a pentavalent molybdenum-doped fully inorganic hole-ordered double perovskite, or a co-doped fully inorganic hole-ordered double perovskite with both tetravalent and pentavalent molybdenum.

[0089] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0090] Unless otherwise specified, the experimental methods used in the following examples are conventional methods. Unless otherwise specified, the materials, reagents, methods, and instruments used are all conventional materials, reagents, methods, and instruments in the art, and can be obtained commercially by those skilled in the art.

[0091] Example 1

[0092] Two mmol of cesium chloride (CsCl, analytical grade), one mmol of tin dichloride (SnCl2, analytical grade), and 0.004 mmol, 0.006 mmol, 0.008 mmol, 0.01 mmol, 0.012 mmol, and 0.014 mmol of molybdenum pentachloride (MoCl5, analytical grade, corresponding to 0.4–1.4 mol% Sn doping), respectively, were placed together in a 25 mL polytetrafluoroethylene (PTFE) liner. Six mL of concentrated hydrochloric acid (37% by mass) was added to the liner, and the mixture was stirred until homogeneous. The PTFE liner was then placed in a 25 mL stainless steel hydrothermal reactor and sealed. The reactor was placed in an oven and heated to 180 °C at a rate of 5 °C / min, and maintained at 180 °C for 12 hours. After the reaction, the reactor was slowly cooled to room temperature at a rate of 10 °C / h. The product in the liner was separated from the mother liquor. The resulting crystals were washed three times with a small amount of anhydrous ethanol to remove surface-adsorbed impurities. Finally, the washed product was dried in an oven at 60℃ until constant weight to obtain the target product. X-ray diffraction analysis was performed on the obtained product, and the results are as follows: Figure 1 As shown. From Figure 1 As can be seen, the main diffraction peak positions of the prepared phosphors with different tetravalent molybdenum doping concentrations correspond well with the diffraction peaks of the cubic Cs₂SnCl₆ standard card PDF#75-0376, indicating that the products have the crystal structure of Cs₂SnCl₆ and are pure phases without obvious impurity peaks. The incorporation of molybdenum did not significantly change the crystal structure of the matrix.

[0093] Example 2

[0094] 1 mmol CsCl, 0.5 mmol SnCl2, and 0.002 mmol MoCl5 (corresponding to 0.4 mol% Sn doping) were placed in a 15 mL polytetrafluoroethylene (PTFE) liner. 3 mL of concentrated hydrochloric acid (37%) was added and mixed thoroughly. The liner was then placed in a 15 mL hydrothermal reactor and sealed. The reactor was heated to 180 °C at a rate of 5 °C / min and maintained for 12 hours, followed by slow cooling to room temperature at a rate of 10 °C / hour. Subsequent treatment was the same as in Example 1. The absorption spectra of the obtained product were measured, and the results are as follows: Figure 2 As shown, the absorption of this phosphor mainly exhibits the characteristic of [MoCl6]. 2- The characteristic absorption peaks of charge migration (CT) transitions were observed. This confirmed that the molybdenum ions doped in the product mainly exist in the +4 valence state, meaning the chemical formula of the product can be written as: Cs₂Sn 0.996 Cl6: 0.4%Mo 4 + .

[0095] Example 3

[0096] 2 mmol CsCl, 1 mmol SnCl2, and 0.010 mmol MoCl5 (corresponding to 1.0 mol% Sn doping) were placed in a 25 mL polytetrafluoroethylene-lined container. 6 mL of concentrated hydrochloric acid (37%) was added and mixed. The reactor was heated to 160 °C at a rate of 3 °C / min and maintained for 15 hours. After the reaction, it was slowly cooled to room temperature at a rate of 30 °C / hour. Subsequent processing was the same as in Example 1 to obtain tetravalent molybdenum-doped Cs2Sn. 0.99 Cl6: 1.0%Mo 4+ Fluorescent powder. The obtained product was observed using a scanning electron microscope (SEM), such as... Figure 3 As shown. From Figure 3 As can be seen, the prepared phosphor is mainly composed of polygonal micron-sized particles, with particle sizes ranging from a few micrometers to hundreds of micrometers. The surface is relatively smooth, and some particles exhibit good crystal properties.

[0097] Example 4

[0098] 2 mmol CsCl, 1 mmol SnCl2, and 0.004 mmol MoCl5 (corresponding to 0.4% Sn doping) were placed in a polytetrafluoroethylene-lined container, mixed with 10 mL concentrated hydrochloric acid, and then placed into a 25 mL hydrothermal reactor. The reactor was heated to 200 °C at a rate of 3 °C / min and held for 10 hours, followed by slow cooling to room temperature at a rate of 10 °C / hour. Subsequent processing was the same as in Example 1 to obtain tetravalent molybdenum-doped Cs2Sn. 0.996 Cl6: 0.4%Mo 4+ Phosphor. Among them... Figure 4 The image shows the fluorescence emission spectrum of the synthesized phosphor at an excitation wavelength of 310 nm. Figure 4 The results show that the phosphor can simultaneously emit near-infrared I light centered at 718nm and covering 700-800nm, and near-infrared II light centered at 1350nm and covering 1200-1600nm.

[0099] Comparative Example 1

[0100] 2 mmol CsCl, 1 mmol tin tetrachloride hydrate (SnCl4·5H2O), and 0.004 mmol MoCl5 (corresponding to 0.4 mol% Sn doping) were placed in a polytetrafluoroethylene-lined container, mixed with 6 mL concentrated hydrochloric acid, and then transferred to a 25 mL hydrothermal reactor. The reactor was heated to 180 °C at a rate of 5 °C / min and maintained for 12 hours, followed by slow cooling to room temperature at a rate of 10 °C / hour. After the crystals separated from the acid solution, they were washed three times with a small amount of ethanol and finally dried in an oven at 60 °C. Figure 5 This is the absorption spectrum of the synthesized phosphor. As can be seen from the figure, the phosphor contains [MoOCl5].2- The associated charge-transfer (CT) and dd transition absorption peaks confirm that the phosphor contains [MoOCl5]. 2- It has an octahedral group and the molybdenum ions it does have are in the +5 valence.

[0101] Example 5

[0102] Two mmol of cesium chloride (CsCl, analytical grade), one mmol of tin tetrahydrate (SnCl4·4H2O, analytical grade), and 0.004 mmol, 0.006 mmol, 0.008 mmol, 0.01 mmol, 0.012 mmol, and 0.014 mmol of molybdenum pentachloride (MoCl5, analytical grade, corresponding to 0.4–1.4 mol% Sn doping), respectively, were placed together in a 25 mL polytetrafluoroethylene (PTFE) liner. Six mL of concentrated hydrochloric acid (37%, mass fraction) was added to the liner, and the mixture was stirred until homogeneous. The PTFE liner was then placed in a 25 mL stainless steel hydrothermal reactor and sealed. The reactor was placed in an oven and heated to 180 °C at a rate of 5 °C / min, and maintained at 180 °C for 12 hours. After the reaction, the reactor was slowly cooled to room temperature at a rate of 10 °C / h. The product in the liner was separated from the mother liquor. The obtained crystals were washed three times with a small amount of anhydrous ethanol to remove surface-adsorbed impurities. Finally, the washed product was dried in an oven at 60°C to constant weight to obtain the target product. X-ray diffraction analysis of the obtained product was performed, and the results are as follows: Figure 6 As shown. From Figure 6 As can be seen, the main diffraction peak positions of the prepared phosphors with different pentavalent molybdenum doping concentrations correspond well with the diffraction peaks of the standard card PDF#75-0376 for cubic Cs₂SnCl₆, indicating that the products have the same crystal structure as Cs₂SnCl₆ and are pure phases without obvious impurity peaks. The incorporation of molybdenum did not significantly change the crystal structure of the matrix.

[0103] Example 6

[0104] 1 mmol CsCl, 0.5 mmol SnCl4·4H2O, and 0.002 mmol MoCl5 (corresponding to 0.4 mol% Sn doping) were placed in a 15 mL polytetrafluoroethylene (PTFE) liner. 3 mL of concentrated hydrochloric acid (37%) was added and mixed thoroughly. The liner was then placed in a 15 mL hydrothermal reactor and sealed. The reactor was heated to 180 °C at a rate of 5 °C / min and maintained for 12 hours, followed by slow cooling to room temperature at a rate of 10 °C / hour. Subsequent treatment was the same as in Example 5. The absorption spectra of the obtained product were measured, and the results are as follows: Figure 7 As shown, the absorption of this phosphor mainly exhibits [MoO] x Cl 6-x ]2- The product exhibits characteristic absorption peaks, including strong charge-transfer (CT) transition absorption and weak dd transition absorption peaks. This confirms that the molybdenum ions doped in the product mainly exist in the +5 oxidation state and that the matrix contains O, meaning the chemical formula of the product can be written as: Cs₂Sn 0.996 (O 0.004 Cl 5.996 ):0.4%Mo 5+ .

[0105] Example 7

[0106] 2 mmol CsCl, 1 mmol SnCl4·4H2O, and 0.010 mmol MoCl5 were placed in a 25 mL polytetrafluoroethylene-lined container. 6 mL of concentrated hydrochloric acid (37%) was added and mixed. The reactor was heated to 160 °C at a rate of 3 °C / min and maintained for 15 hours. After the reaction, it was slowly cooled to room temperature at a rate of 30 °C / hour. Subsequent processing was the same as in Example 5 to obtain pentavalent molybdenum-doped Cs2Sn. 0.99 (O 0.01 Cl 5.99 ):1.0%Mo 5+ Fluorescent powder. The obtained product was observed using a scanning electron microscope (SEM), such as... Figure 8 As shown. From Figure 8 As can be seen, the prepared phosphor is mainly composed of polygonal micron-sized particles, with particle sizes ranging from a few micrometers to tens of micrometers. The surface is relatively smooth, and some particles exhibit good crystal properties.

[0107] Example 8

[0108] 2 mmol CsCl, 1 mmol SnCl4∙4H2O, and 0.004 mmol MoCl5 were placed in a polytetrafluoroethylene-lined container, mixed with 10 mL of concentrated hydrochloric acid, and then placed into a 25 mL hydrothermal reactor. The reactor was heated to 200 °C at a rate of 3 °C / min and held for 10 hours, followed by slow cooling to room temperature at a rate of 10 °C / hour. Subsequent processing was the same as in Example 5 to obtain pentavalent molybdenum-doped Cs2Sn. 0.996 (O 0.004 Cl 5.996 ):0.4%Mo 5+ Fluorescent powder. Figure 9 The fluorescence emission spectrum of the phosphor synthesized in Example 8 is obtained when the excitation wavelength is 310 nm. Figure 9 The results show that the phosphor can simultaneously emit visible light centered at 575 nm and covering the 450-750 nm range, and near-infrared light centered at 950 nm and covering the 800-1200 nm range. The total spectral half-width is 312 nm.

[0109] Comparative Example 2

[0110] 2 mmol CsCl, 1 mmol tin dichloride (SnCl2), and 0.004 mmol MoCl5 were placed in a polytetrafluoroethylene-lined container, mixed with 6 mL concentrated hydrochloric acid, and then transferred to a 25 mL hydrothermal reactor. The reactor was heated to 180 °C at a rate of 5 °C / min. o The solution was kept at C for 12 hours, then slowly cooled to room temperature at a rate of 10°C / hour. After the crystals separated from the acid solution, they were washed three times with a small amount of ethanol and finally dried in an oven at 60°C. Figure 10 This is the absorption spectrum of the synthesized phosphor. As can be seen from the figure, the phosphor contains [MoCl6]. 2- The associated charge-transfer (CT) transition absorption peaks confirm that the phosphor contains [MoCl6]. 2- It has an octahedral group and the molybdenum ions it does have are in the +4 valence.

[0111] Example 9

[0112] 2 mmol of cesium chloride (CsCl, analytical grade), 0.5 mmol of tin dichloride (SnCl2, analytical grade), 0.5 mmol of tin tetrachloride hydrate (SnCl4·5H2O, analytical grade), and 0.004 mmol of molybdenum pentachloride (MoCl5, analytical grade, corresponding to 0.4 mol% Sn doping) were placed in a 25 mL polytetrafluoroethylene (PTFE) liner. 6 mL of concentrated hydrochloric acid (37% by mass) was added to the liner, and the mixture was stirred until homogeneous. The PTFE liner was then placed in a 25 mL stainless steel hydrothermal reactor and sealed. The reactor was placed in an oven and heated to 180 °C at a rate of 5 °C / min, and maintained at 180 °C for 12 hours. After the reaction, the reactor was slowly cooled to room temperature at a rate of 10 °C / hour. The product in the liner was separated from the mother liquor. The resulting crystals were washed three times with a small amount of anhydrous ethanol to remove surface-adsorbed impurities. Finally, the washed product was dried in an oven at 60℃ until constant weight to obtain the target product. X-ray diffraction analysis was performed on the obtained product, and the results are as follows: Figure 11 As shown. From Figure 11 As can be seen, the main diffraction peak positions of the prepared phosphor correspond well with the diffraction peaks of the standard card PDF#75-0376 of cubic phase Cs₂SnCl₆, indicating that the product has the same crystal structure as Cs₂SnCl₆ and is a pure phase without obvious impurity peaks. The incorporation of molybdenum did not significantly change the crystal structure of the matrix, and its chemical formula can be expressed as Cs₂SnCl₆. 0.996 (O 0.002 Cl 5.998 ):0.2%Mo 4+ 0.2%Mo 5+ .

[0113] Example 10

[0114] 1 mmol CsCl, 0.25 mmol SnCl2, 0.25 mmol SnCl4·5H2O, and 0.002 mmol MoCl5 (corresponding to 0.4 mol% Sn doping) were placed in a 15 mL polytetrafluoroethylene (PTFE) liner. 3 mL of concentrated hydrochloric acid (37%) was added and mixed thoroughly. The liner was then placed in a 15 mL hydrothermal reactor and sealed. The reactor was heated to 180 °C at a rate of 5 °C / min and held for 12 hours, followed by slow cooling to room temperature at a rate of 10 °C / hour. Subsequent treatment was the same as in Example 9. The absorption spectra of the obtained product were measured, and the results are as follows: Figure 12 As shown, the phosphor exhibits absorption characteristics similar to [MoCl6]. 2- Charge migration (CT) and [MoOCl5] 2- The characteristic absorption peak of the dd transition was observed. This confirms that the molybdenum ions doped in the product exist simultaneously in both +4 and +5 oxidation states, and that the matrix contains oxygen. Therefore, the chemical formula of the product can be written as Cs₂Sn. 0.996 (O 0.002 Cl 5.998 ):0.2%Mo 4+ 0.2%Mo 5+ .

[0115] Example 11

[0116] 2 mmol CsCl, 0.8 mmol SnCl2, 0.2 mmol SnCl4·5H2O, and 0.010 mmol MoCl5 (corresponding to 1.0 mol% Sn doping) were placed in a 25 mL polytetrafluoroethylene-lined container. 6 mL of concentrated hydrochloric acid (37%) was added and mixed. The reactor was heated to 160 °C at a rate of 3 °C / min and maintained for 15 hours. After the reaction, it was slowly cooled to room temperature at a rate of 30 °C / hour. Subsequent processing was the same as in Example 9 to obtain a phosphor co-doped with tetravalent and pentavalent molybdenum, with the chemical formula Cs2Sn. 0.99 (O 0.002 Cl 5.998 ):0.8%Mo 4+ 0.2%Mo 5+ The obtained product was observed using a scanning electron microscope (SEM), such as... Figure 13 As shown. From Figure 13 As can be seen, the prepared phosphor is mainly composed of polygonal micron-sized particles, with particle sizes ranging from a few micrometers to tens of micrometers. The surface is relatively smooth, and some particles exhibit good crystal properties.

[0117] Example 12

[0118] 2 mmol CsCl, 1 mmol tin raw material (SnCl2:SnCl4 = 8:2, 6:4, 4:6, 2:8), and 0.010 mmol MoCl5 (corresponding to 1.0 mol% Sn doping) were placed in a polytetrafluoroethylene liner, mixed with 10 mL concentrated hydrochloric acid, and then placed in a 25 mL hydrothermal reactor. The reactor was heated to 200 °C at a rate of 3 °C / min and held for 10 hours, followed by slow cooling to room temperature at a rate of 10 °C / hour. Subsequent processing was the same as in Example 9, yielding four different tetravalent and pentavalent molybdenum co-doped phosphors with the chemical formulas Cs2Sn. 0.99 (O 0.002 Cl 5.998 ):0.8%Mo 4+ 0.2%Mo 5+ ;Cs2Sn 0.99 (O 0.004 Cl 5.996 ):0.6%Mo 4+ 0.4%Mo 5+ ;Cs2Sn 0.99 (O 0.006 Cl 5.994 ):0.4%Mo 4+ 0.6%Mo 5+ ;Cs2Sn 0.99 (O 0.008 Cl 5.992 ):0.2%Mo 4 + 0.8%Mo 5+ .in Figure 14 The fluorescence emission spectra of the four phosphors synthesized in Example 12 were obtained at an excitation wavelength of 310 nm. Figure 14 The results show that the emission spectra of these four phosphors can all cover the visible-near infrared light range of 500-1600 nm.

[0119] Comparative Example 3

[0120] Two mmol of CsCl, one mmol of tin tetrachloride hydrate (SnCl4·5H2O), and 0.004 mmol of MoCl5 (corresponding to 0.4 mol% doping of Sn) were placed in a polytetrafluoroethylene-lined container, mixed with 6 mL of concentrated hydrochloric acid, and then transferred to a 25 mL hydrothermal reactor. The reactor was heated to 180 °C at a rate of 5 °C / min and maintained for 12 hours, followed by slow cooling to room temperature at a rate of 10 °C / h. After the crystals separated from the acid solution, they were washed three times with a small amount of ethanol and finally dried in an oven at 60 °C to obtain Cs2Sn doped only with pentavalent molybdenum. 0.996 (O 0.004 Cl 5.996 ):0.4%Mo 5+ Phosphor. Among them... Figure 15 The emission spectrum of the phosphor synthesized in Comparative Example 3 is shown when the excitation wavelength is 310 nm. Figure 15 The phosphor emits visible light in the range of 450-750 nm and near-infrared light in the range of 800-1200 nm.

[0121] Comparative Example 4

[0122] 2 mmol CsCl, 1 mmol tin dichloride (SnCl2), and 0.004 mmol MoCl5 (corresponding to 0.4 mol% doping of Sn) were placed in a polytetrafluoroethylene-lined container, mixed with 6 mL of concentrated hydrochloric acid, and then placed in a 25 mL hydrothermal reactor. The reactor was heated to 180 °C at a rate of 5 °C / min and maintained for 12 hours, followed by slow cooling to room temperature at a rate of 10 °C / h. After the crystals separated from the acid solution, they were washed three times with a small amount of ethanol and finally dried in an oven at 60 °C to obtain Cs2Sn doped only with tetravalent molybdenum. 0.996 Cl6: 0.4%Mo 4+ Phosphor. Among them... Figure 16 The emission spectrum of the phosphor synthesized in Comparative Example 4 is shown when the excitation wavelength is 310 nm. Figure 16 The phosphor emits near-infrared light in the 700-800nm ​​and 1200-1600nm ranges.

[0123] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the technical solution of the present invention, and are not intended to limit the specific implementation of the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the claims of the present invention should be included within the protection scope of the claims of the present invention.

Claims

1. A molybdenum-doped all-inorganic hole-ordered double perovskite, characterized in that, The molybdenum-doped all-inorganic hole-ordered double perovskite is a tetravalent molybdenum-doped all-inorganic hole-ordered double perovskite, and the chemical formula is Cs2Sn 1-x Cl6:xMo 4+ wherein 0.1%≤x≤5%.

2. The molybdenum-doped all-inorganic hole-ordered double perovskite of claim 1, wherein, The fluorescence emission spectrum of the tetravalent molybdenum doped full inorganic hole ordered double perovskite is 700-800nm and 1200-1600nm; and / or, The absorption spectrum of the tetravalent molybdenum doped full inorganic hole ordered double perovskite is 250-450nm.

3. A method of preparing the molybdenum-doped all-inorganic hole-ordered double perovskite of claim 1 or 2, characterized in that, CsCl, SnCl2 and MoCl5 are mixed, concentrated hydrochloric acid is added, mixed, and then subjected to hydrothermal reaction, cooling, separation, washing, and drying to obtain the tetravalent molybdenum doped full inorganic hole ordered double perovskite.

4. A molybdenum-doped all-inorganic hole-ordered double perovskite, characterized in that, The molybdenum-doped all-inorganic hole-ordered double perovskite is a pentavalent molybdenum-doped all-inorganic hole-ordered double perovskite, and the chemical formula is Cs2Sn 1-y (O y Cl 6-y ):yMo 5+ , wherein 0.1%≤y≤5%.

5. The molybdenum-doped all-inorganic hole-ordered double perovskite of claim 4, wherein, The fluorescence emission spectrum of the pentavalent molybdenum doped full inorganic hole ordered double perovskite is 450-750nm and 800-1200nm; and / or, The absorption spectrum of the pentavalent molybdenum doped full inorganic hole ordered double perovskite is 250-370nm.

6. A method of preparing the molybdenum-doped all-inorganic hole-ordered double perovskite of claim 4 or 5, characterized in that, CsCl, SnCl4.4H2O and MoCl5 are mixed, concentrated hydrochloric acid is added, mixed, and then subjected to hydrothermal reaction, cooling, separation, washing, and drying to obtain the pentavalent molybdenum doped full inorganic hole ordered double perovskite.

7. A molybdenum-doped all-inorganic hole-ordered double perovskite, characterized in that, The molybdenum-doped all-inorganic hole-ordered double perovskite is a quadrivalent molybdenum and pentavalent molybdenum co-doped all-inorganic hole-ordered double perovskite, and a chemical formula is Cs2Sn 1-a-b (O b Cl 6-b ):aMo 4+ ,bMo 5+ , wherein 0.1%≤(a+b)≤5%, and .

8. The molybdenum-doped all-inorganic hole-ordered double perovskite of claim 7, wherein, The fluorescence emission spectrum of the tetravalent molybdenum and pentavalent molybdenum co-doped full inorganic hole ordered double perovskite covers a range of 500-1600nm; and / or, The absorption spectrum of the tetravalent molybdenum and pentavalent molybdenum co-doped full inorganic hole ordered double perovskite is 250-450nm.

9. A method of preparing the molybdenum-doped all-inorganic hole-ordered double perovskite of claim 7 or 8, characterized in that, CsCl, SnCl2, SnCl4.4H2O and MoCl5 are mixed, concentrated hydrochloric acid is added, mixed, and then subjected to hydrothermal reaction, cooling, separation, washing, and drying to obtain the tetravalent molybdenum and pentavalent molybdenum co-doped full inorganic hole ordered double perovskite.

10. An optoelectronic device, characterized by The light-emitting material of the photoelectric device is the molybdenum doped full inorganic hole ordered double perovskite according to any one of claims 1-9.

11. Use of the molybdenum doped full inorganic hole ordered double perovskite according to any one of claims 1, 2, 4, 5, 7, 8 in the fields of product detection, anti-counterfeiting, safety monitoring, non-destructive analysis, light-emitting LED, solar cell, temperature detector, multi-spectral imaging, ultra-wideband light source, or wide-spectrum photoelectric detector.

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