Preparation,Characterization And Photoelectric Properties Of CuInSe₂ Quantum Dot

CuInSe₂?CISe?quantum dots have high optical absorption coefficient(¹0⁵ cm^-1)and 1.04 eV optical bandgap,therefore,they have great application prospects as optical absorption layer of solar cells.CuInSe₂,Zn-doped CuInSe₂ and ZnS-coated CuInSe₂ quantum dots were prepared by solvothermal method.The effects of different reaction conditions on the size,morphology,uniformity,composition,phase structure and photoelectric properties of the quantum dots were studied by TEM,SEM,EDS,XRD,U-V and PL spectroscopy.The results are as follows:?1?CuInSe₂ quantum dots were synthesized by solvothermal method.When CuI,InCl₃·4H₂O and Se powder were used as raw materials,octadecene and oleamine as solvents with the reaction temperature of190?and the of reaction time 4.5 h,CuInSe₂ quantum dots in chalcopyrite structure with a size of about 7 nm and uniform distribution were prepared.?2?Zn-CuInSe₂ alloy quantum dots were synthesized by adding Zn?OAc?₂ as Zn source in the preparation solution of CuInSe₂ quantum dots.The effect of doped Zn on CuInSe₂ was studied.Alloy quantum dots with chalcopyrite structure were synthesized under the experimental conditions of temperature of 200?,reaction time of 6 h and Zn/CuIn=0.3.It was found that the size of CuInSe₂ quantum dots doped with Zn is about 12 nm.?3?ZnS-CuInSe₂ core-shell structure quantum dots were prepared by solvothermal method using Zn?Ac?₂,thiourea and Na₂S as raw materials.TEM test results showed that the size of the quantum dot was about 15nm,and the emission peak was obviously enhanced,which realized the tuning of the light absorption and emission of quantum dots.?4?Quantum dot sensitized solar was assembled.Mesoporous TiO₂thin films in thicknesses of 13?m were prepared by screen printing.Oil-to-water operation was made on quantum dots with 3-mercaptopropionic acid?MPA?.After pretreatment with 10?L MPA and 50?L NaOH?10%?solution,they were adsorbed onto mesoporous TiO₂ thin films as photoanodes,Na₂S and S as electrolytes,and copper sheets as electrodes to form batteries.