A kind of high fluorescence efficiency inorganic non-lead perovskite material and preparation method

Abstract

The invention relates to an inorganic non-lead perovskite material with high fluorescence efficiency and a preparation method thereof, which belong to the technical field of preparation of perovskite crystal materials. The high fluorescence efficiency inorganic non-lead perovskite material is Cu-doped Cs 2 AgI 3 Perovskite, the doping amount of Cu is 0.09%. The preparation method is: first mix cesium iodide and silver iodide, then ball mill, then add cuprous iodide, hydroiodic acid, microliter hypophosphorous acid and seal and heat at 150-200°C. Finally, after cooling down to room temperature and annealing, cooling at -10°C to -35°C for 1h to 3h, Cs with high purity and enhanced fluorescence efficiency can be obtained 2 AgI 3 : Cu crystal, which emits bright blue fluorescence under the excitation of 302nm ultraviolet lamp, has the advantages of lead-free, chromium-free, high quantum efficiency and environmental stability.

Description

technical field [0001] The invention belongs to the technical field of preparation of perovskite crystal materials, in particular to a method for significantly increasing Cs by doping Cu 2 AgI 3 Quantum efficiency, synthetic Cs 2 AgI 3 : Cu blue fluorescent material method. Background technique [0002] Renewable energy includes solar energy, water energy, wind energy, biomass energy, wave energy, tidal energy, ocean temperature difference energy, geothermal energy, etc. These energy sources are recyclable and renewable in nature, and are inexhaustible. If these energies can be utilized, it will greatly promote the development of human society. Therefore, photovoltaic cells that directly convert sunlight into electricity are of considerable interest. By the end of 2012, the cumulative installation of photovoltaics in the world reached about 100GWp (gigawatts). Among the solar cells in the world, 85% are crystalline silicon solar cells, and the rest are polycrystalline...

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Problems solved by technology

However, this double-layer perovskite will lead to an increase in the non-radiative recombination pathways of electrons and holes, which will reduce the fluorescence efficiency.

[0004] In 1949, the Clarabrink group prepared Cs for the first time. 2 AgI 3 This substance, due to the poor solubility of silver iodide, the synthesis needs to introduce potassium iodide under high temperature conditions, and prepare it into a concentrated solution to promote the dissolution of raw materials. This method cannot avoid the impact of excess KI on crystal purity.

In 2004, S. Hull's group also synthesized Cs by solid phase high temperature melting method. 2 AgI 3 , the method is complicated to operate, consumes a lot of energy, takes a long time, and is not conducive to large-scale industrial production

In 2020, Xie's group prepared lead-free and cadmium-free bimetallic Cs-Ag-X (X=Cl, Br, I) halides for the first time by ball milling, realizing a spectrum ranging from ultraviolet-visible to near-infrared (390 to 820nm) Wide range of tuning, the study found that in order to prepare bright yellow fluorescent Cs 2 AgI 3 A certain amount of silver acetate must be added as a photoinitiator, and Cs with fluorescent properties cannot be obtained simply by ball milling cesium iodide and silver iodide. 2 AgI 3

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