Polythiophene/mesoporous SrTiO3 nanocomposites with enhanced photocatalytic activity under visible light

In this contribution, a facile synthesis of polythiophene (PTh), using various ratios of thiophene (Th) monomers, mesoporous SrTiO3 nanocomposites has been achieved through in-situ oxidative polymerization method. XRD patterns exhibit well-defined, sharp crystalline SrTiO3 structure. XPS, FTIR and Raman spectra clearly revealed the formation of PTh-SrTiO3 nanocomposites. HRTEM and FESEM images confirmed that the PTh-SrTiO3 structure is quite similar to the undoped SrTiO3 with fine nanoparticles size in the range of 10-20 nm. PTh-SrTiO3 nanocomposites possessed type IV isotherm that is characteristic for mesoporous materials. BET surface area values of 0.5, 1 and 10 wt% PTh doped SrTiO3 are 118.00 m(2)/g, 126.66 m(2)/g and 72.36 m(2)/g, respectively. The photocatalytic performance of PTh-SrTiO3 nanocomposites for MB photodegradation was performed and compared with either pure PTh or undoped SrTiO3 under visible light illumination. The photocatalytic efficiency of the PTh-doped SrTiO3 nanocomposites is superior to that of either pure PTh or undoped SrTiO3. 1% PTh-SrTiO3 nanocomposite exhibits the highest photocatalytic performance with more than 90% MB photo degradation. The photodegradation rate of 1% PTh-SrTiO3 nanocomposite is greater 4.75 times than that of pure PTh or undoped SrTiO3. This is explained by its large surface area, synergetic effect that led to efficient separation of the photogenerated charge carriers, low band gap energy and mesoporous structure.