Design method of Z-type heterojunction catalyst for high-efficiency photocatalytic decomposition of water

Abstract

The invention discloses a design method of a Z-type heterojunction catalyst for high-efficiency photocatalytic decomposition of water. The method comprises the following steps: (1) calculating a work function and an energy band of a band polar material, and extracting a conduction band bottom, a valence band top and a vacuum energy level in the energy band; (2) constructing a heterostructure of the material with polarity according to the size of the work function of the material with polarity and the relative positions of the conduction band bottom, the valence band top and the vacuum energy level, performing structure optimization on the heterostructure, and calculating the energy band of the heterojunction; and (3) obtaining an energy band bending mode of the heterojunction according to the energy band of the heterojunction, and taking the heterojunction with the maximum energy band bending as the Z-type heterojunction. According to the method, the Z-type heterojunction photocatalyst is designed by utilizing the polar material through a DFT calculation method, so that the photocatalytic efficiency is improved, and a guiding effect is provided for designing the high-efficiency Z-type heterojunction photocatalyst.

Description

technical field [0001] The invention relates to the field of photocatalysis, in particular to a design method of a high-efficiency direct Z-type heterojunction photocatalyst. Background technique [0002] With the continuous development of social industrialization, environmental pollution and energy crisis have become two problems that human beings need to solve urgently in the 21st century. Solar energy is the most widely obtained and cheapest renewable energy on the earth. Using solar energy to produce energy and eliminate pollution is considered to be the best solution to the above two problems. Therefore, people are committed to converting solar energy into other forms of energy that can be applied through various technologies such as photocatalysis, solar cells, and photoelectrochemical cells. Among them, photocatalysis is considered to be one of the most promising light conversion technologies because it can directly convert solar energy into clean fuels such as hydro...

AI Technical Summary

Problems solved by technology

[0003] Two-dimensional transition metal dichalcogenides (2D TMDCs) are stable in the atmosphere and have a suitable light absorption bandgap, making them a good choice as efficient photocatalysts, but their structural symmetry along the out-of-plane direction cannot be used very effectively. Separation of photogenerated carriers, which limits photocatalytic conversion efficiency

At present, researchers have proposed Type 2, Z-type and other types of catalytic mechanisms, and have designed many heterojunctions, making good progress, but the catalytic efficiency is still far from meeting the requirements of actual production.

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