Abstract：Perovskite solar cells(PSCs) are paid much attention due to simple preparation and high photoelectric conversion efficiency. Carbon nanofiber films(CNFs) prepared by electrospinning have high specific surface area, electrical properties and chemical stability, but the application in PSCs is limited due to their brittleness. The flexible and conductive Ag/ZrO2/C composite nanofiber films were prepared by electrospinning and hydrothermal method. After that, it was applied as the counter electrode of flexible PSCs and the effect of Ag nanoparticles with different concentrations on the performance of the composite nanofiber films and the PSCs were studied. The results show that when the concentration of precursor solution rises from 0 g/mL to 0.030 g/mL, the coating effect of Ag nanoparticles on the Ag/ZrO2/C composite nanofiber improves obviously and all the composite nanofiber films display the excellent flexibility and modulus of elasticity (0.479 MPa), meanwhile, the conductivity of the films increases from 866 S/m to 4862 S/m, so as to enhance the hole-electron transport capacity of the films and the performance of flexible PSCs. When the solution concentration is 0.030 g/mL, the PSCs have best photoelectric conversion efficiency(PCE) of 6.05% and optimal current density (18.44 mA/cm2). It is of great significance to further improve the performance of flexible PSCs and the application of flexible carbon nanofiber films.
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