A facile synthesis of titanium dioxide/reduced graphene oxide composite with high photocatalytic activity for removal of gaseous formaldehyde

In order to obtain photocatalyst with high performance for the removal of indoor gaseous formaldehyde (HCHO), effective titanium dioxide/reduced graphene oxide (TiO2/rGO) composite was synthesized by a simple and mild one-step water bath method. The properties of the as-prepared TiO2/rGO composite were characterized by x-ray diffraction (XRD), transmission electron microscope (TEM), x-ray photoelectron spectroscopy (XPS), N-2 adsorption/desorption isotherm and Fourier transform infrared (FT-IR) spectroscopy. In this work, Polyvinylpyrrolidone (PVP) was used to avoid the reunion of rGO sheets during the preparation process. The obtained 1-PVP-TiO2/2-rGO composite exhibited enhanced photocatalytic performance on low concentration gaseous HCHO removal at the optimal addition of PVP and GO. It could eliminate 72% of HCHO in 9 h, which is 3.5 times higher than bare TiO2. The TEM results exhibited that the stacking of rGO sheets could be well controlled and P25 nanoparticles were anchored on the surface of rGO with good dispersion. The enhancement should be attributed to the inhibition on the agglomeration of rGO sheets after the reduction reaction and more TiO2 nanoparticles were loaded on the rGO nanosheets. Moreover, the produced chemical combination between the TiO2 nanoparticles and rGO sheets could greatly promote the electronic transmission. The energy-saving preparation method and outstanding photocatalytic performance could make the catalyst more promising for indoor air purification.