Eur. Phys. J. Appl. Phys. 96, 30104 (2021)
https://doi.org/10.1051/epjap/2021210171

Regular Article

Tailored TiO₂ nanorod arrays for dye sensitized solar cell applications

¹ Department of Physics, Karunya Institute of Technology and Sciences, Coimbatore 641114, India
² Department of Physics, Hindustan Institute of Technology and Science, Chennai 603103, India

^* e-mail: j.beula85@gmail.com

Received: 7 August 2021
Received in final form: 20 October 2021
Accepted: 23 November 2021
Published online: 24 December 2021

Abstract

A TiO₂ layer using titanium (IV) butoxide on fluorine doped tin oxide (FTO) substrate is used as a seed layer for the growth of TiO₂ nanorod arrays (TRA). TRAs with length of ∼1 to 2 μm were grown on seed layer (SL) by two step method. In the first step TiO₂ SLs were deposited by sol-gel assisted spin coating method and the second step involved the typical hydrothermal technique to grow rutile TRAs. Most of the TRAs grown on FTO substrate without SL were randomly oriented and TRAs with 0.025 M SL was oriented vertically from the substrate. Whereas TRAs grown on 0.05 M SL showed hierarchical nanoflower clusters composed of a bunch of TRAs as petals blooming from the core. The XRD pattern showed all the three TRAs to be crystallized in a tetragonal rutile phase. Photo luminescence spectra revealed that the TRAs on 0.05 M SL have comparatively low intense blue emission band, predicting the suppressed electron-hole recombination rate. The power conversion efficiency of the dye sensitized solar cell (DSSC) with TRAs grown on 0.05 M SL was recorded as 3.18%, which is 3 times greater than that without SL and 1.6 times greater than that with 0.025M SL in our observations.