Two-dimensional lead-free perovskite material and design method

Abstract

The invention discloses a two-dimensional lead-free perovskite material and a design method. The structural formula of the two-dimensional lead-free perovskite material is expressed as: AxByXz, wherein x = 1, 2, 3; y = 1, 2 ; Z = 4, 7, 8, 9; A is one element of Cs, Ba, Sr, and Ca; B is one element of Sb, Bi, Ga, In, Au, Sn, Hf, Zr, amd Ti; X is one element of F, Cl, Bre, I, S, Se, and Te. A firstprinciple method that is widely used, accurate in computation, and low in cost is used to systematically compute the excellent properties of such structure, and two types of perovskite materials, including transcending solar photovoltaic star material MAPbI3 and a graphene-like semiconductor with graphene linear electronic dispersion and an intrinsic quasi-particle bandgap of about 0.1 to 1 eV, are found out.

Description

technical field [0001] The invention relates to the technical fields of energy and semiconductor materials, in particular to a two-dimensional lead-free perovskite material and a design method. Background technique [0002] With the continuous development of science and technology and the continuous progress of society, energy problems have become increasingly prominent, and the development of the semiconductor industry has also reached a certain bottleneck period. Perovskite materials, as a hot material that has received more and more attention in recent years, have shown many excellent properties, and have played a vital role in both energy issues and the development of the semiconductor industry. [0003] First of all, regarding energy issues, since solar energy is an inexhaustible clean energy source, it is an important countermeasure for us to pursue sustainable development. Solar cells are a way to directly convert solar energy into electrical energy, and have attract...

AI Technical Summary

Problems solved by technology

At present, the most mainstream light-absorbing layer material of perovskite solar cells is methylamine lead iodide (MAPbI 3 ) as the representative lead-based hybrid perovskite, although its properties are good, there are still two problems to be solved on the road to industrialization: 1. The current perovskite materials have poor stability and are exposed to Light, heat, or water and oxygen environments can easily lead to unstable device performance; 2. Lead-based perovskite materials contain highly toxic element lead, which pollutes the environment and can cause irreversible damage to the human nervous system

The successful preparation of graphene has opened the door to the two-dimensional world. As an ideal material for nano-optoelectronic devices, graphene has ultra-high carrier mobility (10 4 -10 5 cm 2 V -1 the s -1 ), but its zero bandgap greatly limits its application in the semiconductor industry

At present, people mainly solve this problem in two ways: first, open the bandgap value of graphene through a series of external conditions such as doping, strain, electric field, and construction of heterojunction; Difficulty maintaining graphene's linear electron dispersion and ultrahigh mobility while opening the bandgap

At present, the external quantum efficiencies of green, red, and near-infrared LEDs are 20.3%, 21.3%, and 20.7%, respectively, while the external quantum efficiency of blue LEDs is only 6.2%.

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