Photoelectrode thin film of dye-sensitized solar cell fabricated by anodizing method and spin coating and electrochemical impedance properties of DSSC

The paper studies the photoelectrode thin film of dye-sensitized solar cell (DSSC) fabricated by anodizing method, explores the structure and properties of the fabricated photoelectrode thin film, measures the photoelectric conversion efficiency of DSSC, and finds the electrochemical impedance properties of DSSCs assembled by photoelectrode thin films in different thicknesses. Besides, in order to increase the specific surface area of nanotubes, this paper deposits TiO2 nanoparticles (TNP) on the surface of titanium oxide nanotube (TNT). As shown in experimental results, the photoelectric conversion efficiency of the DSSC fabricated by the study rises to 6.5% from the original 5.43% without TnB treatment, with an increase of photoelectric conversion efficiency by 19.7%. In addition, when the photoelectrode thin film is fabricated with mixture of TNTs and TNP in an optimal proportion of 2:8 and the photoelectrode thin film thickness is 15.5 μm, the photoelectric conversion efficiency can reach 7.4%, with an increase of 36.7% from the original photoelectric conversion efficiency at 5.43%. Besides, as found in the results of electrochemical impedance analysis, the DSSC with photoelectrode thin film thickness at 15.5 μm has the lowest charge-conduction resistance (Rk) value 9.276 Ω of recombined electron and conduction resistance (Rw) value 3.25 Ω of electrons in TiO2.

Graphical abstractThis paper studies the photoelectrode thin film of dye-sensitized solar cell (DSSC) fabricated by anodizing method, and finds the electrochemical impedance properties of DSSCs assembled by photoelectrode thin films in different thicknesses. Experimental results show that when the photoelectrode thin film is fabricated with mixture of TNTs and TNP in an optimal proportion of 2:8 and the photoelectrode thin film thickness is 15.5 μm, the photoelectric conversion efficiency can reach 7.4%, with an increase of 36.7% from the original photoelectric conversion efficiency at 5.43%. Besides, as found in the results of electrochemical impedance analysis, the DSSC with photoelectrode thin film thickness at 15.5 μm has the lowest charge-conduction resistance (Rk) value 9.276 Ω of recombined electron and conduction resistance (Rw) value 3.25 Ω of electrons in TiO2.Download full-size imageHighlights► The titanium oxide (TiO2) nanotubes with length of 10-25 μm and diameter of 100 nm prepared by two-step anodic treatment. ► TiO2 nanoparticles (TNP) deposit on the wall surface of TiO2 nanotubes FROM titanium (IV) n-butoxide (TnB) aqueous solution. ► The photoelectric conversion efficiency of the DSSC rises to 6.5% from the original 5.43% without TnB treatment. ► The photoelectric conversion efficiency can reach 7.4% after TiO2 nanotubes were mixed with TNP in an optimal proportion of 2:8.