This paper describes a novel chemical method for preparing SiO_2/TiO_2 Janus particles.First,polystyrene(PSt)/SiO_2 particles with a raspberry-like structure are prepared by electrostatic assembly.The influences of the reaction time of sulfonation and the treatment times of polyelectrolyte solutions(PDADMAC,PSS)on PSt and SiO_2 are investigated with respect to the surface charge density of the particles.SiO_2/TiO_2 Janus particles are then obtained by hydrolysis of butyl titanate on the surface of PSt/SiO_2 particles followed by a calcination process.Particle size analyzer,Zeta potential instrument,FTIR,TEM and SEM are used to characterize the particle size,the amount of charge on the surface of PSt and SiO_2 particles and the compositions and morphologies of PSt/SiO_2,SiO_2/TiO_2 and PSt/SiO_2/TiO_2.The diameters of the PSt,SiO_2,PSt/SiO_2 and SiO_2/TiO_2 particles are 2.0 μm,303 nm,2.7 μm and 330nm,respectively.
Baoliang ZhangQiuyu ZhangHepeng ZhangXinlong FanDezhong YinXiangjie LiWei Li
