Study On The Synthesis And Photoeletric Response Of Ternary Sulfide Semiconductor Nanomaterials

The ternary sulfide semiconductor nanomaterials show a luxuriant composition,structure and performance,as well as multi-field application prospects.At present,for the rational design and controlled synthesis of such materials,opportunities and challenges coexist,especially the preparation of one-dimensional linear and rod-shaped nanostructures.This article focuses on the preparation of ternary sulfide one-dimensional nanomaterials and carries out major research work in order to understand and control the growth process of one-dimensional nanocrystals from the crystal growth mechanism.Firstly,combining the structure-driven crystal anisotropy growth mechanism and the alloying mechanism of equivalent ion replacement,a ternary(Sb_1-xBi_x)₂S₃nanowires/s were synthesized.Secondly,Bi₂S₃ nanorods as templates were used to chemical conversion synthesis of ternary BiSI nanorods.At the end of the dissertation,solvothermal synthesis of ternary sulfide Zn-In-S was attempted,and the hierarchical structure of its nanosheet was assembly obtained.In addition to material synthesis,the thesis also includes the characterization and tunning of the photoelectric response performance of the resulting ternary sulfide.The specific research contents are summarized as follows:1)Ternary alloy continuous solid solution(Sb_1-xBi_x)₂S₃?0<x<1?with one-dimensional nanostructures?wires and rods?was synthesized through solvothermal process.In the experiment,ethylene glycol was used as the solvent.By changing the ratio of Bi/Sb reactants,solvothermal synthesis of ternary(Sb_1-xBi_x)₂S₃ solid solution nanowires/rods with aspect ratio and adjustable band gap.When the Bi/Sb ratio is low,the product exhibits a nanowire with a high aspect ratio,and when the Bi/Sb ratio is high,the product is a nanorod with a low aspect ratio.The formation of ternary solid solution is attributed to the binary Sb₂S₃ and Bi₂S₃ with the same crystal structure and similar unit cell constant,that is,the alloying mechanism driven by heterogeneous isomorphism.The obtained ternary solid solution(Sb_1-xBi_x)₂S₃ nanowires/rods exhibited component-related light absorption and good light response behavior under visible light irradiation.2)Bi₂S₃ nanorod template was transformed to synthesize BiSI one-dimensional nanorods with high photoconductivity,and we explored the photoelectric properties of BiSI.The Bi₂S₃nanorods were first prepared by the reflux method,and converted into ternary BiSI nanorods with high crystallinity through the combined reaction with BiI₃ in ethanol solution.The mechanism of this synthesis process is due to the template effect of the nanorods.Compared with the binary Bi₂S₃template,the ternary BiSI has high light absorption intensity and large band gap value?¹.5 eV?.Evaluation of the performance of ITO/BiSI/ITO sandwich optoelectronic devices shows that BiSI nanorods exhibit excellent light absorption and light response behavior under irradiation of visible light or monochromatic light.3)Ternary Zn-In-S hierarchical structure materials assembled from nanosheets were synthesized through solvothermal process.We explored the effect of element content on product phase,morphology and performance by changing the ratio of Zn,In,S elements in the precusor.The morphology characterization and phase analysis of the materials are carried out through various testing techniques.The microscopic morphology was analyzed by SEM and TEM,and it was confirmed that the sample was composed of nanosheets.As the S content in the precursor increases,the absorbance of the sample increases and the band gap value gradually decreases.The constructed ITO/Zn-In-S/ITO sandwich device exhibits an excellent photoconductivity response under visible light irradiation,indicating that the obtained material has the value of research in photodetection and photocatalysis.