The development of low-cost, new solar cell key materials and high-performance devices is the key to large-scale development of solar cells to solve future social energy problems, but also one of the hot and difficult research in this field. With the support of the National Natural Science Foundation, the Ministry of Science and Technology and the Chinese Academy of Sciences, researchers at the Key Laboratory of Molecular Nanostructures and Nanotechnology, Institute of Chemistry, Chinese Academy of Sciences, recently designed and constructed highly efficient quantum dot sensitization based on three-dimensional conductive networks and assembly structures Solar cell materials, and low-cost thin-film solar cell materials research has made new progress. The design and fabrication of ITO @ Cu2S nanowire arrays assembled from ITO nanowire core and Cu2S nanocrystal shell have shown that quantum dot-sensitized solar cells fabricated using this material with a three-dimensional conductive network structure exhibit superior performance to traditional materials (Nano Lett., 2014, 14, 365). The influence of the interface between the ITO nanowire core and the Cu2S nanocrystalline shell on the cell performance of Cu2S nanocomposites (ACS Appl. Mater. Interfaces, 2014, 6, 15448); on this basis, through the networked multi-level assembly design, based on the ITO @ Cu2S nanowire array structure on the basis of two And the tertiary structure further enhances the conversion efficiency of the quantum dot-sensitized solar cell using the counter electrode material to 6% or more. The new pair of electrode materials can effectively form a tunnel junction during battery operation, greatly improving the conversion efficiency of the battery by reducing the series resistance of the device, increasing the shunt resistance and the fill factor, and solving the problem that the traditional metal copper / cuprous sulfide is easy to fall off , The challenge of not being able to work steadily (Nano Lett., 2015, 15, 3088). To explore low-cost thin film solar cell materials is the only way to large-scale use of solar power generation. FeS2 is a kind of material with low toxicity and abundant reserves and has suitable forbidden band width, light absorption coefficient and sufficient carrier diffusion length, so it is an ideal low-cost environment-friendly thin-film solar cell material one. One of the keys to its final application is the development of a low-cost synthesis method for the preparation of pure cubic FeS2 material that is stable in air. Recently, researchers in nanotechnology labs have successfully developed a method for the preparation of stable, pure cubic FeS2 micro- and nano-materials in the air based on solution-oriented aggregation. It is found that spherical FeS2 nanocrystals, FeS2 nanocubes and microspheres assembled with FeS2 nanocrystals can be controlled by solvent induction. Spherical aberration correction electron microscopy and other techniques were used to clearly characterize the growth of FeS2 initial nanocrystals. The systematic study on Raman spectroscopy shows that the FeS2 material with many morphologies exposed to air for at least 1 year can be obtained by selecting the appropriate solvent, which lays a good foundation for further research on low cost thin film solar cells based on FeS2 material (J. Am Chem. Soc., 2015, 137, 2211). Figure ITO @ Cu2S nanowire array as a highly efficient quantum dot sensitized solar cell electrode material diagram