TiO2-ZnO rodlike nanocomposite as photoanode in DSSC yielding 7.38% PEC with N3 dye

Abstract The agglomeration of TiO₂-ZnO nanocomposite is a well-established strategy to apprehend various energy photons from the solar spectrum. This research article focuses on direct chemical precipitation protocol for rod-like TiO₂-ZnO NPs of different TiO₂:ZnO molar ratios for solar energy harvesting using N3 dye. The synthesized nanocomposites were evidenced with various analytical probing techniques. X-ray diffraction scrutiny corroborated rutile and hexagonal wurtzite crystal structure for TiO₂ and ZnO respectively. Surface morphology depicted nanorod texture with varying diameters and widths whereas elemental analysis studies confirmed optimal stoichiometry for the presence of Ti, O, and Zn, respectively. The optical energy gap was evaluated using UV-visible spectroscopy was between 2.95 to 3.00 eV. A 2D electron diffraction pattern was captured with the SAED technique to reveal nanocrystalline TiO₂-ZnO nanocomposite. Among the samples synthesized, composite having TiO₂:ZnO having 3:1 ratio showcased good performance in solar energy conversion registering Jsc = 3.25 mA/cm², Voc = 946.96 mV, FF of 48% with PEC of 7.38% in an unadulterated aqueous 0.1 M I⁻/ I₃⁻ electrolyte under 100 mW/cm² irradiation while EIS investigation resulted in Rs = 3.17 cm², Rct = 20.14 cm², Cdl (10⁻⁹) = 40.25 F/cm² and Zw (10⁻⁵) = 3.27 mMho.