Synthesis and application in solar cell of poly(3-octylthiophene)/titania nanotubes composite

Amorphous titania nanotubes with diameters between 20 and 30 nm were successfully synthesized by hydrothermal method using anatase TiO2 as the precursor and 10 M NaOH as the mine to the agent. A conducting polymer composite, poly(3-octylthiophene)/titania nanotubes (P3OT/TiO2NTs) was synthesized by situ-chemical method. Transmission electron microscope (TEM) and scanning electron microscope (SEM) depicted the morphology of the samples, defining that TiO2NTs were successfully coated by poly(3-octylthiophene) molecules. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (IR) showed the chemical interaction of poly(3-octylthiophene) and titania nanotubes in the composite. Cyclic voltammetry (CV) curves showed that the forbidden band gap of the P3OT/TiO2NTs composite is 0.672 eV, realizing the complementary advantages of n and p semiconductor. Ultraviolet–visible spectra (UV–vis) and fluorescence spectra (PL) showed that its optical performance is far superior to poly(3-octylthiophene) and titania nanotubes separately. Solar cell was sensitized by P3OT/TiO2NTs. A solar-to-electric energy conversion efficiency of 0.593% was attained with the system.