Cu2ZnSnS4（CZTS）具有吸收系数高、毒性低及元素储量丰富的优点，是十分有潜力的光电功能材料。然而，较低的光电效率限制其在太阳能电池、光电催化等领域的应用。如何调控CZTS材料成分、结构，改善光电性能是亟需解决的问题。自掺杂仅通过掺杂半导体自身元素，改善光吸收和电荷传输特性，可避免外来元素掺杂引起的晶格失配等问题，是提高光电性能简单有效的手段。本项目基于前期工作，提出利用基于胶体化学制备技术的自掺杂策略调控CZTS材料的成分和缺陷，优化能带结构，进而提高光电性能。具体通过调节Cu、Zn、Sn离子掺杂量和掺杂位置，探明自掺杂CZTS纳米晶的生长机制；采用低成本制膜技术，开发高效自掺杂CZTS薄膜，总结自掺杂对光电性能的影响规律；结合实验与理论研究，阐明自掺杂影响CZTS光电性能的内在根源。本项目不仅可丰富自掺杂改性的方法和理论，还可推动CZTS性能的优化，为构建高效光电器件奠定基础。

Cu2ZnSnS4 (CZTS) has been considered as one of the most promising photoelectric materials due to its high absorption coefficient, low toxicity, and abundant elements. However, the low photoelectric efficiency limits its application in the research fields such as solar cell and photoelectrocatalysis. Developing effective routes to modify the composition, structure, and property is an urgent issue to be solved. Self-doping, a facile and efficient technique to improve the light absorption and charge transfer, can boost the photoelectric property, while the potential adverse impact by doping with extraneous elements, for instance, lattice mismatch, can be avoided. On the basis of the previous work, in this project we propose a colloid-chemistry based self-doping strategy to tune the composition, defect, and band structure of CZTS, so as to promote the photoelectric property. By regulating the doping amount and doping site of Cu, Zn, and Sn ions, the growth mechanism of self-doped CZTS nanocrystals can be firstly illustrated. Efficient self-doped CZTS films can be subsequently fabricated through low-cost deposition routes, and the influence of self-doping on the photoelectric property should be discussed. Based on the experimental and theoretical results, the intrinsic origins of the enhanced photoelectric property by self-doping can be clarified. It is expected that this project not only can enrich the methods and theories of self-doping, but also can boost the photoelectric property of CZTS, so as to lay the groundwork for constructing highly efficient photoelectric devices.