Synthesis And Propetries Of Cu-base Ternary, Pb-base Binary Nanocrystsls

The ever increasing demand for energy resources continues to drive thedevelopment of cost-effective and high-efficiency photovoltaic materials. TheI-III-VI family of semiconductors, including CuInS₂, CuInSe₂, CuIn_xGa_1-xSe₂andCuGaSe₂, have large absorption coefficients, good photostability and the appropriatebandgaps that match well with the solar spectrum. Therefore, they are expected totake the place of toxic CdS and CdTe to be highly efficient and promisingphotovoltaic materials. In the present thesis, we successfully synthesize CuGaSe₂nanocrystals （NCs） via the solvothermal method. Through controlling the differentselenium precursors, chalcopyrite CuGaSe2NCs with controllable size andmorphology are achieved. The crystal structure and shape of the prepared CuGaSe₂NCs are characterized by the powder X-ray diffraction （XRD）, the transmissionelectron microscope （TEM） and scanning electron microscope （SEM）. Meanwhile,we preliminary study the optical properties of the as-obtained CuGaSe2NCs.In addition, as an important IV-VI semiconductor materials, PbSe has attractedmuch attention due to the considerable applications in the infrared detection,optoelectronics, and thermoelectric material. We introduce a green chemical strategyto prepare the cubic phase PbSe NCs. Therein, PbO and Se are employed as thecorresponding precursors, as well as olive oil is used as the ligand and solvent,respectively. The cubic phase PbSe NCs are obtained via the normal injection andanti-injection routes.We believe that the present methods will provide references for the furtherinvestigations on the synthesis and properties of CuGaSe2and PbSe NCs.