来源丰富及直接带隙约2.0 eV的Cu2O半导体材料可作为太阳能电池吸收材料，理论上太阳能转化效率可达20%。 但因为Cu2O薄膜的高电阻及多晶结构，其实际转化效率仍较低。 本项目将研究发展低成本的外延电沉积方法制备p-Cu2O/n-Cu2O同质结外延单晶薄膜,以期提高其太阳能转化效率。 我们将系统研究阳离子或阴离子掺杂对Cu2O半导体薄膜的导电性能及光吸收性能的影响，理解其控制规律和内在机理，优化条件，提高其导电性和光吸收率。 系统研究溶液和电化学条件对外延薄膜表面和界面结构的影响及内在机制，优化条件，获得高质量的同质结外延薄膜。 研究建立同质结外延薄膜的表面/界面结构和太阳能转化效率的关系。 通过本项目的研究将为制备无毒、高效率及低成本的氧化物薄膜太阳能电池提供新原理和工作基础，促进太阳能电池研究领域的发展。

Cuprous oxide(Cu2O)is an attractive solar cell active materials due to its direct band gap around 2.0 eV and high absorption coefficient,combined with materials abundance,nontotoxicity and low cost fabrication. The theoretical efficiency for Cu2O is about 20%. However,the current actural highest conversion efficiency is pretty low due to high resistivity and polycrystal structure of the Cu2O thin films. The proposed project will develop low cost epitaxial electrodeposition method to fabricate nontoxic,stable and high efficient p-Cu2O/n-Cu2O epitaxial homojunction thin films. We will systematicly study and optimize the cation and anion dopants on increasing of optical absorption and electric conductivity of electrodeposited Cu2O thin films and try to understand their underneath mechanism. We will also systematicly explore and optimize the solution conditions and electrochemical conditions on growth of the high quality epitaxial homojunction interface structure and try to understand underneath mechanism of these effects. We will also try to build the relationship between the homogeneous epitaxial structure and conversion efficiency. The result of the proposed project will new principle for fabrication of the nontoxic,high efficient and low cost oxide thin film solar cell and push the development of the high efficient new generation solar cell.