SYNTHESIS OF CuInSe2(CIS) NANOSHEETS BY TWO LIQUID PHASE METHODS AND PHOTOELECTRIC PROPERTIES OF CIS THIN FILMS

Taking the all-green synthesis of copper indium selenium (CIS) material as the research purpose, we took Vitamin C (Vc) as a reducing agent and triethylene glycol (TEG) as a solvent to synthesize copper indium selenium(CIS) materials by solvothermal method and hot injection method, and discussed the advantages and disadvantages of the two synthetic methods. The dosage of Vc used in the two preparation methods was investigated, the process and mechanism of the chemical reaction were explained, and the thin film of the synthesized product was prepared and characterized. The experimental results showed that both liquid phase methods can be used to synthesize the single-phase chalcopyrite CIS nanosheets, and the performance of the product synthesized by the hot injection method was superior to that by the solvothermal method. The copper-poor structure Cu0.9In0.94Se2 nanosheets with a band gap of 1.06 eV were synthesized by hot injection method. The carrier concentration and carrier mobility of the thin film prepared by the product synthesized by the hot injection method reached 1.08×1016 cm-3 and 120.62 cm2 V -1 S -1 , respectively. The results showed that using Vc as a reducing agent, both liquid phase methods could be applied to produce single-phase chalcopyrite CIS nanosheets, which could achieve the universal use of Vc in liquid phase synthesis of CIS materials. Moreover, the products synthesized by hot injection method were more conducive to the preparation of high-performance thin films.