Improving Photovoltaic Performance of Dye-Sensitized Solar Cell by Modification of Photoanode With g-C3N4/TiO2 Nanofibers

In order to improve the photovoltaic performance of dye-sensitized solar cell (DSSC), graphitic carbon nitride (g-C
₃
N
₄
)/titanium dioxide (TiO
₂
) nanofibers (NFs) are added into the photoanode of DSSC as an additional layer. g-C
₃
N
₄
is prepared by high-temperature calcination. Through sol–gel method and electrospinning technology, we prepare g-C
₃
N
₄
/TiO
₂
NFs. The material properties of g-C
₃
N
₄
/TiO
₂
NFs are characterized through X-ray diffraction (XRD), ultraviolet-visible (UV-Vis), and field emission scanning electron microscope (FE-SEM). From the measurements of electrochemical impedance spectroscopy (EIS), incident photon to current efficiency (IPCE), and
${J}-{V}$
characteristics, the performances of the DSSCs are analyzed, including impedance parameters, short-circuit current density, open-circuit voltage, fill factor, and photoelectric conversion efficiency. The results show that the addition of g-C
₃
N
₄
/TiO
₂
NFs is able to enhance the photovoltaic performance. The photoelectric conversion efficiency of the modified DSSC is increased to 5.22%. Compared with the photoelectric conversion efficiency of the DSSC without modification (4.11%), it is an increase of 27%.