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以 TiN 为钛源和氮源,采用水热法分别以H 2 SO 4、HCl、HNO 3为介质合成了 N-TiO 2纳米粉末,研究了介质及水热反应温度对 N-TiO 2晶型、形貌、粒径及光催化性能的影响。 SEM、XRD 表明, H 2 SO 4为介质得到粒状锐钛矿 N-TiO 2,HCl、HNO 3为介质得到棒状金红石 N-TiO 2,粒径 d (HCl)＞d (HNO 3)＞d (H 2 SO 4),相同介质中,粒径随反应温度的升高而增大。 XPS、HRTEM 表明,N 元素以O—Ti—N 键形式掺杂,使得 TiO 2晶格间距变大。 UV-Vis 表明,N 掺杂降低了 TiO 2的禁带宽度,感光范围拓展到可见光区。可见光催化降解实验表明,催化效率η(H 2 SO 4)＞η(HNO 3)＞η(HCl),相同介质中,光催化效率随反应温度的升高而降低。

Nitrogen-doped titanium dioxide (N-TiO 2 )nanopowders were prepared by hydrothermal synthesis in H 2 SO 4 ,HCl,HNO 3 using the titanium nitride (TiN)as both titanium resource and nitrogen resource.Effects of solvent medium and hydrothermal temperature on the crystalline type,morphology,size and the photocata-lytic activities of the product was investigated.The SEM,XRD result shows that granular anatase TiO 2 was ob-tained in H 2 SO 4 ,while rod-like rutile TiO 2 could be obtained in HCl and HNO 3 ,the crystalline size was as fol-lows:d (HCl)>d (HNO 3 )>d (H 2 SO 4 ),it largens with increasing hydrothermal temperature in the same sol-vent medium.Nitrogen atoms are doped into TiO 2 lattice,form a new bond of O—Ti—N resulting in an in-crease of the lattice distance,which are confirmed by XPS,HRTEM.The narrow of band-gap and the visible-light response are due to nitrogen doping,which are shown by UV-Vis spectra analysis.The experiments of photodegradation of methyl orange show that,the photocatalytic activities was as follows:η(H 2 SO 4 )>η(HNO 3 )>η(HCl),it lessens with increasing hydrothermal temperature in the same solvent medium.