Preparation and performance of dye-sensitized solar cells based on ZnO-modified TiO2 electrodes

Abstract

The ZnO-modified TiO 2 electrode was prepared by adding Zn(CH 3 COO) 2 ·2H 2 O to the TiO 2 colloid during the sol-gel production process, and was used in dye-sensitized solar cells (DSCs). The open circuit voltage (V OC ) and fill factor (ff) of the cells were improved significantly. The performances of the ZnO-modified TiO 2 electrode such as dark current, transient photocurrent, impedance, absorption spectra, and flat band potential (V fb ) were investigated. It is found that the interface charge recombination impedance increases and V fb shifts about 200 mV toward the cathodic potential. The effect mechanism of ZnO modification on the performance of DSCs may be that ZnO occupies the surface states of the TiO 2 film.

Co-sensitization of TiO 2 -MWCNTs hybrid anode for efficient dye-sensitized solar cells

“…The first semicircle represents the inter face resistance of electrons at counter electrode/electrolyte (R 1 ), second signifies the interface resistance at the photoanode / electrolyte (R 2 ), and the third indicates the diffusion process of I À /I 3 À redox couple in electrolyte (Zw) [41,42]. Only second arc comes out in the Nyquist plot in the Fig 5. It is probable that the other two arcs corresponding to R 1 and Zw are overshadowed by large semicircle reprenting R 2 [43,44]. The R 2 is related to the charge recombination rate, e.g., a smaller R 2 indicates a faster charge recombination.…”

Photoelectrochemical splitting of water to produce a power appetizer Hydrogen: A green system for future –( A short review)

“…The flat band potential which is a key factor of PEC splitting of water can also be modified by using layered oxides because one oxide can occupy the surface states of other resulting in increased photoresponse 41 . Core -shell made by embedding metal nanoparticles in semiconductor material offers better response as it reduce recombination of charge carriers by forming an energy barrier and also increase the porosity.…”

Improving the efficiency of dye sensitized solar cells by TiO2-graphene nanocomposite photoanode

“…The first semicircle represents the charge transport resistance at counter electrode/electrolyte (R 1 ), second signifies the charge transport resistance at the photoanode / electrolyte interface (R 2 ), and the third indicates the diffusion process of redox couple in electrolyte (Zw) [26,33]. Only second arc comes out in the Nyquist plot in the Fig 5. It is probable that the other two arcs corresponding to R 1 and Zw are overshadowed by larger semicircle reprinting R 2 [34,35]. The R 2 is related to the charge recombination rate, e.g., a high R 2 value shows a lower charge recombination and vise versa.…”