Dye-sensitized solar cells based on composite TiO2 nanoparticle-nanorod single and bi-layer photoelectrodes

Abstract

TiO2 nanoparticle (NP), composite TiO2 nanoparticle-nanorod (NP-NR) and bi-layer TiO2 nanoparticle/nanorod (NP/NR) with the optimized diameter of NRs had been prepared as anode layer in dye-sensitized solar cells (DSSCs). Morphology and thickness of anode layers were provided by field emission scanning electron microscope (FE-SEM) and scanning electron microscopy (SEM) devices. Current density-voltage diagrams were prepared by potentiostat and solar simulator devices at air mass (AM) 1.5. It is determined that DSSCs based on composite NP-NR photoelectrode had the best conversion efficiency of 5.07%. Also, the results of the electrochemical modelling of these DSSCs indicated that solar cells based on NP-NR electrode had the highest electron transport time (? d) of 312.87 ms, electrons' recombination lifetime (? n) of 130.4 ms and the lowest transfer resistance (Rct) as well as transport resistance (Rt) of 22.46 and 9.4 respectively.