A Study Of Hydrogen Production Efficiency From A2-MWS₄ Heterojunction By Solar Photocatalytic Splitting Of Water

Hydrogen production by solar photocatalytic hydrolysis,as a green hydrogen production technology,does not consume secondary energy other than solar energy and provides a sustainable development solution for hydrogen energy production.The high cost of photocatalyst,narrow effective light absorption range and low hydrogen precipitation efficiency limit the application of solar photolytic hydrogen production in industrial fields.The relationship between the electronic properties,optical excited state properties and lattice dynamics properties of transition metal sulfide heterojunction-based photocatalysts and hydrogen precipitation efficiency was investigated.The structure of AA-Mo S₂/WSe₂（A2-MWS₄）photolytic hydrogen production catalyst with low cost,high stability,wide spectral effective response and high efficiency was obtained.The main research of this paper is as follows.In the first part,Mo S₂ catalytic activity is negatively correlated with stability.Based on the introduction of WSe₂ modulation by Mo S₂,a photocatalytic hydrogen precipitation heterogeneous structure was constructed using density function theory and hybrid function,structural geometry optimization,and kinetic stability analysis were performed to obtain a stable photolytic hydrogen precipitation catalyst A2-MWS₄ with a binding energy of-0.36 e V,an intra-layer distance of 3.90（?）,and an applied ambient temperature of 500 K.In the second part,the A2-MWS₄ broad spectral response solar energy utilization light absorption range.To address the problems of narrow effective light absorption range and low absorption rate of the catalyst in the current study.The relationship between the electronic properties and optical excited state properties of A2-MWS₄ and the hydrogen precipitation efficiency of A2-MWS₄ was investigated by using the first principle and the multi-body Grignard function to obtain the A2-MWS₄ with 62%narrowing of the effective electronic band gap,26%increase of the static dielectric constant,79%reduction of the photogenerated electron-hole Coulomb force,21%extension of the photogenerated carrier lifetime and five times broadening of the solar spectral absorption range catalyst structure.In the third part,the influence of A2-MWS₄ lattice dynamics properties on hydrogen precipitation performance.The effect of phonon scattering on the light absorption efficiency under photothermal effect is not clear,the phonon dispersion parameters of A2-MWS₄ lattice dynamics are calculated,and the effect of phonon Ridley decay on the hydrogen precipitation performance is analyzed,and it is concluded that the A2-MWS₄ phonon decay of 6 me V energy has a facilitating effect on the A2-MWS₄ hydrogen precipitation reaction.