Enhanced photocatalytic activity of wool-ball-like TiO₂ microspheres on carbon fabric and FTO substrates

^a School of materials science and engineering, Hubei University of Automotive Technology, Shiyan, 442002, P.R. China.
^b College of Engineering and Applied Sciences, Nanjing Univerisy, Nanjing 210093, China.
^c Institute of Materials Engineering, Nanjing University, Nantong 226019, Jiangsu, P. R. China.

^* Corresponding author: zhangy@huat.edu.cn

Abstract

The wool-ball-like TiO₂ microspheres on carbon fabric (TiO₂-CF) and FTO substrates (TiO₂-FTO) have been synthesized by a facile hydrothermal method in alkali environment, using commercial TiO₂ (P25) as precursors. The XRD results indicate that the as-prepared TiO₂ have good crystallinity. And the SEM images show that the wool-ball-like TiO₂ microspheres with a diameter of 2-3 μm are composed of TiO₂ nanowires, which have a diameter of ~50 nm. The photocatalytic behavior of the wool-ball-like TiO₂ microspheres, TiO₂-CF and TiO₂-FTO under ultraviolet light was investigated by a pseudo first-order kinetic model, using methyl orange (MO) as pollutant. The wool-ball-like TiO₂ microspheres obtained a degradation rate constant (K_ap) of 6.91×10^-3 min^-1 . The K_ap values of TiO₂-FTO and TiO₂-CF reach 13.97×10^-3 min^-1 and 11.80×10^-3 min^-1, which are 2.0 and 1.7 times higher than that of pristine wool-ball-like TiO₂ microspheres due to the “sum effect” between TiO₂ and substrates. This study offers a facile hydrothermal method to prepare wool-ball-like TiO₂ microspheres on CF and FTO substrates, which will improve the recyclability of phtocatalysts and can be extended to other fields.