硫掺杂TiO_2空心球制备及光催化性能研究

Preparation and photocatalysis property of sulfur doped TiO_2 hollow spheres

以聚苯乙烯-丙烯酸羟乙酯共聚(P(StHEA))微球为模板、钛酸四丁酯和硫脲为主要原料,制备了硫掺杂二氧化钛(S-TiO2)空心球,采用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线衍射仪(XRD)和X光电子能谱(XPS)表征产物的形貌、晶型以及硫元素的掺杂状态,并以甲醛溶液模拟废水,研究了S-TiO2空心球的紫外光催化性能。结果表明,煅烧去除了P(St-HEA)微球模板,成功得到TiO2空心球,硫元素掺杂对TiO2空心球的粒径和形貌影响不大。STiO2空心球锐钛矿型晶粒的尺寸缩小,晶型由纯的锐钛矿型转化为锐钛矿/金红石型混合晶型。硫脲引入的硫离子,以S4+状态取代TiO2晶粒中的Ti4+离子,形成Ti1-xSxO2固溶体。S-TiO2空心球光催化性能优于TiO2空心球,且空心球的光催化性能优于粉体P25。STiO2空心球在紫外光下照射2 h,降解甲醛的催化效率为60%。

Sulfur-doped titanium dioxide( S-TiO2) hollow spheres were prepared by the reaction of tetrabutyl titanate and thiourea as the main raw material with polystyrene-hydroxyethyl acrylate copolymer( P( St-HEA)) microspheres templates. The morphology,crystal type and state of elemental sulfur doping of S-TiO2 hollow spheres was characterized by scanning electron microscopy( SEM),transmission electron microscopy( TEM),X-ray diffraction( XRD) and X-ray photoelectron spectroscopy( XPS). Study the catalytic properties of S-TiO2 hollow spheres using methanal solution simulated wastewater. The results showed that TiO2 hollow spheres were obtained by removing P( St-HEA) microspheres template successfully,the particle size and morphology of TiO2 hollow spheres are little effected by sulfur-doping,the crystallite dimension of TiO2 hollow spheres diminished and the crystal shape of TiO2 hollow spheres was changed from pure anatase into anatase / rutile. Sulphur was present in the form of S4 +which substitutes Ti4 +in the titania lattice,forming Ti1- xSxO2 solid solution. The performance of photocatalysis of doped sample was superior to the pure TiO2 hollow spheres,while they both preceded TiO2 powder. The catalytic efficiency of synthesized photocatalyst was 60% for degrading methanal under UV-light.