Synthesis and properties of Ce-doped TiO2-reduced graphene oxide nanocomposite

Abstract

A nanocomposite of Ce-doped TiO2-reduced graphene oxide (CedT/RGO) was synthesized to evaluate the synergistic effects of constituents on electrical and photoelectric properties. The nanoparticles of titania and CedT were synthesized via the sol-gel method. Then, RGO was prepared using a new version derived from the Hammer's method and hydrothermal methods. Finally, CedT/RGO nanocomposite was synthesized applying hydrothermal method. The nanoparticles and nanocomposite were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, Field emission scanning electron microscopy (FESEM), Energy dispersive X-ray spectroscopy and elemental mapping. Then, diffuse reflectance and photoluminescence spectroscopy were conducted to study photoelectric and photoluminescence behavior. Finally, electrical conductivity measurement showed that the electrical conductivity of CedT/RGO nanocomposite was increased from 4.6 (μS/cm) to 81.3 (μS/cm). In addition, the absorption spectrum of the nanocomposite was shifted toward visible wavelengths. The band gap of the titania was reduced from ∼3.2 eV to ∼2.65 eV in CedT nanoparticles and it was further reduced to ∼1.95 eV in the CedT/RGO nanocomposite. The FESEM results of the nanocomposite indicated the formation of CedT nanoparticles, smaller than 50 nm, on the RGO sheets. These data indicate that this nanocomposite can be suitable for electrical, photoelectric, photocatalytic and sensing applications.