Novel preparation method of nitrogen-doped TiO2 hollow particles by the reaction crystallization in refined droplet

We succeeded in fabricating the uniform spherical titanium oxide (TiO2) hollow particles improved photocatalytic activity by doping nitrogen under visible light irradiation using new processing. To prepare the uniform spherical nitrogen-doped TiO2 particles with monodispersed size distribution and monodispersed pore distribution, we performed the reaction crystallization within the confined droplet by inkjet nozzle. The absorption edge of the TiO2 particles shifted to the lower wavelength side with an increase in the sintering temperature. TiO2 particles prepared by an inkjet process exhibited spherical porous structures with uniform size distribution, resulting that this process would be controllable to nitrogen-doped TiO2 particles. The results indicated that the chemical states of the nitrogen doping and the light absorption characteristics of the TiO2 particles could be controlled by the sintering temperature.