Bilayered ZnO/Nb2O5 photoanode for dye sensitized solar cell

Abstract

Nb2O5 layer were deposited on ZnO by using doctor blade method. The preparation of a bilayered ZnO/Nb2O5 photoanode was introduce for dye-sensitized solar cell (DSSC) application. Deposition of Nb2O5 layer on ZnO film improves power conversion efficiency of DSSCs. The ZnO/Nb2O5photoanode-based DSSCs show increase in photocurrent, open circuit voltage and conversion efficiency. The ZnO/Nb2O5 solar cell provides 50 mV increase of open circuit voltage, [Formula: see text] increment in current density and [Formula: see text] increment in efficiency as compare to ZnO-based DSSCs. We further analyzed the electron recombination properties of ZnO and ZnO/Nb2O5 by utilizing electrochemical impedance spectroscopy (EIS). The EIS analysis (Bode Plot) for ZnO/Nb2O5 photoanode show shifting of the peak related to electron recombination towards low frequency as compared to ZnO photoanode. Thus, there is an increase in lifetime of electrons in the ZnO/Nb2O5 photoanode, confirming that the recombination reactions are reduced in ZnO/Nb2O5 photoanode as compared to the ZnO.