Enhanced Photovoltaic Performance of Nanostructured Hybrid Solar Cell Using Highly Oriented TiO₂ Nanotubes

Abstract

Highly oriented TiO2 nanotubes have been fabricated using ZnO nanorod template through liquid reactive deposition on the ITO substrates. The diameter and length of TiO2 nanotubes can be effectively controlled for the suitable use for a hybrid solar cell by varying the diameter and length of the ZnO nanorod template. A mixture of P3HT/PCBM was infiltrated into the gaps between TiO2 nanotubes to form hybrid solar cells. The open circuit voltage, short circuit current density, fill factor, and power conversion efficiency of the hybrid solar cell using highly oriented TiO2 nanotubes were 646 mV, 9.95 mA cm−2, 51.6%, and 3.32%, respectively, much higher than 1.2% of hybrid solar cell based on ZnO nanorods tested under otherwise identical conditions and significantly higher than 0.7% of the same type hybrid solar cells reported in literature. The enhancement of the power conversion efficiency could be resulted from the highly oriented TiO2 nanotubes with smaller diameter and large specific surface area for the efficient electron transfer in hybrid solar cells.