Preparation And Optical Properties Of The Series Nanomaterials Of CuInS₂/Cu-In-Zn-S

Because of a series of excellent physical and chemical properties aswell as optoelectronic devices and biomedical applications, metalchalcogenide semiconductor nanomaterials have become one of the mostactive research areas on physics, chemistry, materials science and manyother subjects. Systematic development of new metal chalcogenidesemiconductor nanocrystals as well as in-depth study of their optical,magnetic and electrical properties will help give full play to the maximumpotential of this type of material.Previous studies have concluded that the material properties and itsapplication depended not only on the structure of the material itself,crystal, composition of the material itself but its size and morphology alsoplayed a key role in the application. So the controlled synthesis ofdifferent sizes and morphology of semiconductor nanomaterials is not onlytheoretical significance and can be expanded application of nanomaterials. In this paper, a simple, convenient A-Pot method has been used tosynthetize morphology controlled CuInS₂, Cu-In-Zn-S, and the otherchalcogenide semiconductor materials. The linear optical properties andnonlinear optical properties have also to be researched. The main contentsof this article are as follows:（1） We give a brief introduction on nanomaterials and quantum dots,and then describe the synthesis of nanomaterials and applications ofnonlinear optical properties.（2） By A-Pot method to synthesize CuInS₂nanoparticles: whenacetylacetone copper, copper iodide, and copper acetate, to be used coppersource respectively, the testing of TEM found that rod like CuInS₂nanocrystals can be got using acetylacetone copper as copper source.Temperature has an important factor on their particle size control usingiodide copper. The result showed the larger particles with the highertemperature. Through discussion of package agent dosage we founduniformity degree of crystallinity is better when the molar ratio of thiolagents to precursor is40times. By discussing the different packages agentwe found that when using dodecanethiol and size smaller than the excitonBohr radius, CuInS₂nanocrystals can be light. But oil amine and oleic acidas ligand that is susceptible to quench the luminescence of nanocrystallineCuInS₂.（3） Using A-Pot method, different ratio of the precursors, different reaction temperature, and different precursors played a key role inCu-In-Zn-S alloy nanocrystals structure, morphology, and properties. Wealso found that temperature could change the Cu-In-Zn-S alloynanocrystals structure. Setting the ratio of Cu: In: Zn: S=2:1:1:4, thewurtzite Cu-In-Zn-S alloy nanocrystals can be generated. When Cu: In: Zn:S is x: x:2（1-x）:2, chalcogenide Cu-In-Zn-S alloy nanocrystals can begenerated. Different precursors have an impact on the different structureand morphology Cu-In-Zn-S alloy nanocrystals. When Cu: In: Zn: S=x: x:2（1-x）:2, emission spectra can be adjusted from485to740nm byadjusting x （0-1）. Setting the ratio of Cu: In: Zn: S=2:1:1:4, the wurtziteCu-In-Zn-S alloy nanocrystals with emitting in the range from649to777nm can be generated under the240oC. Different structure Cu-In-Zn-Salloy nanocrystals had different third-order optical nonlinear by Z-scan.The third-order nonlinear susceptibilities of chalcogenide and wurtziteCu-In-Zn-S alloy nanocrystals are3.82×10^-12esu,1.11×10^-11esu.