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The mechanism for the deterioration of the lifetime of dye-sensitized solar cell (DSC) is not clear yet, and there is still no effective way to solve the current situation. In this paper, after the DSC device was assembled and lasted for nearly 700 h, the Dyed-NSF/El interface was reconstructed by electrical erasing and the results showed that the photovoltaic performance of the cell could be regenerated. At the same time, electrochemical impedance spectroscopy was used to analyze the changes of internal electron transport and transfer impedance, surface state defects, etc. in the process of degradation and regeneration, and inferred internal causes of cell degradation and regeneration. It was confirmed that the changes in the structure and properties of Dyed-NSF/El interface was the origin of performance degradation. The results of this paper provide a potential technology that could lead to a significant increase in device lifetime and make DSC no longer a disposable cell.

Composed of sub-micron TiO 2 particles, the scattering layer covers the top of the optical active layer composed of nano TiO 2 particles to together form the “optical active layer/scattering layer”, the double-layer skeleton microstructure of the photoanode in dye sensitized solar cells (DSCs). This type of photoanode extends the optical path of the incident light and enables repeated absorption of light, resulting in increase in the efficiency of DSCs. Since the optical active layer and scattering layer are integrally sintered and the materials have homogeneity, the study on influence of the scattering layer on the photoanode performance should not be limited to the optical properties. This paper investigates the non-optical properties of the scattering layer in detail, including electronic distribution, charge accumulation, transport/recombination dynamics, as well as the inherent influence of these properties on DSCs. The results show that the scattering layer can not only reflect light simply, but also has unique the electronic properties. Just like the optical active layer, the scattering layer can accommodate electrons. The electron transit time and lifetime in the scattering layer are faster than those in the optical active layer after the influence caused by the conduction band movement is removed. It is reasonable to infer that the main transport process occurs in the optical active layer and the recombination rate of the scattering layer is higher than that of the optical active layer within a certain bias range in a DSCs with the double-layer skeleton microstructure of the photoanode. So, the recombination process of electrons through the scattering layer may be a potential recombination path under the working conditions.