微波辐照法制备氮掺杂二氧化钛空心球及其光催化性能

以聚（苯乙烯-丙烯酸羟乙酯）［P（St-HEA）］共聚微球为模板制备了二氧化钛空心球（TiO2HS），采用微波法，以水合肼为氮源对空心球进行掺杂，制备了氮掺杂二氧化钛空心球（N-TiO2HS）。采用扫描电子显微镜（SEM）、透射电镜（TEM）、X射线衍射分析（XRD）、X射线光电子能谱（XPS）、紫外可见漫反射光谱分析（UV-vis DRS）等方法表征了N-TiO2HS的形貌、晶型及氮元素的掺杂状态，用重铬酸钾溶液模拟废水，研究了样品的光催化性能。实验结果表明，煅烧去除 P（St-HEA）微球模板，成功得到了TiO2HS。水合肼引入的氮元素以N3-的形态取代了TiO2晶格中O2-离子，形成O-Ti-N键，且掺杂后对TiO2HS的形貌和晶体结构影响不大。N-TiO2HS光催化性能优于TiO2HS，在紫外光下照射 2 h，N-TiO2HS降解重铬酸钾的催化效率为 95.8%，较TiO2HS提高了约25%。

Preparation of Nitrogen Doped TiO2 Hollow Spheres by Microwave Irradiation and Its Photocatalysis Property

Titanium dioxide hollow spheres （TiO2HS） were prepared with polystyrene-hydroxyethyl acrylate ［P（St-HEA）］ copolymer microspheres as templates，which were then doped with hydrazine hydrate as nitrogen source by microwave irradiation method. The nitrogen-doped titanium dioxide hollow spheres （N-TiO2HS） were synthesized as the final products. The morphology，crystal type and state of elemental nitrogen in N-TiO2HS were characterized by scanning electron microscopy，transmission electron microscopy，X-ray diffraction，X-ray photoelectron spectroscopy，ultraviolet visible diffuse reflectance spectra. Photocatalytic properties of the samples under ultraviolet irradiation were investigated with potassium dichromate solution as the simulated wastewater. The results show that TiO2HS are successfully obtained by removing P （St-HEA） microspheres template. The element of nitrogen from hydrazine hydrate presentes in the form of N3- which substitutes O2- in the titania lattice，and formes O-Ti-N bond，however，this exerts little effect on the morphology and crystalline?structure of TiO2HS. The photocatalysis performance of N-TiO2HS is superior to that of the pure TiO2HS. The catalytic efficiency of N-TiO2HS for degradation of potassium dichromate is 95.8% under ultraviolet irradiation for 2 h，which is about 25% higher than that of TiO2HS.