Preparation of titanium dioxide nanorods/nanoparticles via one-step hydrothermal method and their influence as a photoanode material in nanocrystalline dye-sensitized solar cell

Abstract

Titanium dioxide (TiO2) nanostructures composed of nanorods and nanoparticles (NRs/NPs) were prepared via a one-step hydrothermal method. The structural and phase purity of the synthesized products was characterized by powder X-ray diffraction (PXRD) analysis and the result showed anatase phase with good crystalline nature. The surface morphology of the nanostructures has been identified using transmission electron microscopy (TEM) analysis and the results showed nanorods and nanoparticles morphology. The elemental states of TiO2 NRs/NPs were identified using X-ray photoelectron spectroscopy (XPS). In order to quantify the surface area of the synthesized products, nitrogen adsorption and desorption isotherm analysis was used and the surface area of 93.08 m2/g was obtained from the Brunauer–Emmett–Teller (BET) approach. Dye-sensitized solar cell has been fabricated using prepared NRs/NPs. The influence of NRs/NPs in the fabricated device has been tested under the illumination of 1 sun and the performance was compared with commercial P25 nanoparticles. A power conversion efficiency of ∼9% has been found with NRs/NPs employed solar cell. The electrochemical process of the fabricated device was studied under the illumination with the help of electrochemical impedance spectroscopy analysis (EIS) which showed longer lifetime (26·9 ms) and reduced charge recombination at the interface of NRs/NPs and redox couples.