Poly (3-hexylthiophene) sensitized Ag doped TiO2-NTs (P3HT/Ag-TiO2-NTs) have been prepared using the three sequential steps: two step anodization, galvanostatic deposition and spin coating techniques. The morphology and structure of P3HT synthesized by oxidative polymerization with FeCl3 were characterized using NMR, FTIR, SEM, XRD and optical properties of P3HT were investigated using Uv-Vis technique. The characterization results showed that the P3HT has 64.7%HT-HT configuration, mainly edge-on oriented lamellar structure and the optical band gap of 224 eV. Also, the morphology and structure characterization of P3HT/Ag-TiO2-NTs were determined by FE-SEM and XRD. The electrochemical behaviors of P3HT/Ag-TiO2-NTs in acetonitrile electrolyte contained I-/I-3(-) were examined by utilizing Electrochemical Impedance Spectroscopy (EIS) and Cyclic Voltammetry (CV). The EIS results displayed that after the modification with P3HT, the value of charge transfer resistance at -0.4V decreases from 514 Omega cm(2) to 121 Omega cm(2), compared to Ag-TiO2-NTs. Furthermore, the analysis results of EIS and Mott-Schottky for P3HT/Ag-TiO2-NTs under simulated solar light revealed that the charge transfer resistance decreased from 121 Omega cm(2) to 51.60 Omega cm(2) and the carrier density (N-D) increased from 8.69 x 10(21) cm(-3) to 70.1 x 10(21) cm(-3), compared to the values under the absence of solar light. These indicate that P3HT supplies better photogenerated electron-hole pairs separation and mobility. (C) 2017 Elsevier B.V. All rights reserved.