【摘要】 分别以硫代乙酰胺和硝酸为硫源和氮源,通过一步溶剂热法制得硫氮共掺杂改性二氧化钛催化剂,并通过XRD、TEM、XPS、UV-vis、N₂吸附-脱附和光电流测试硫氮共掺杂二氧化钛（SN-TiO₂）的结构、组成和光电性质。结果显示:N和S元素分别以间隙掺杂形成了O-Ti-N键或通过取代晶格结点的Ti⁴⁺形成了Ti-O-S键,从而形成新的杂质能级,得到禁带宽度减小、可见光吸收增强、载流子迁移速率加快的锐钛矿相SN-TiO₂纳米粉。以Cr（Ⅵ）为模拟污染物,评估了A-SN-TiO₂的可见光催化性能,并将其与硫脲为硫源制备的B-SN-TiO₂、S-TiO₂、N-TiO₂和TiO₂的光催化活性进行了对比。光催化和ESR测试结果显示,A-SN-TiO₂具有更高的催化活性,在光照60 min后,A2-SN-TiO₂对Cr（Ⅵ）的还原率高达100%。此外,研究还发现SN-TiO₂可见光催化还原Cr（Ⅵ）的主要活性物质为·O₂^-。更多还原

【Abstract】 An unique one-step solvothermal route,which utilized thioacetamide and nitric acid as the sulphur and nitrogen source,was proposed for the synthesis of S-N co-doped TiO₂ nanocrystals.The structures,composition,BET specific surface area and optical properties of SN-TiO₂ were characterized by X-ray diffraction,X-ray photoelectron spectroscopy,UV-vis diffuse reflectance spectroscopy,N₂ adsorption-desorption isotherms and photocurrent measure.It’s demonstrated that anatase phase SN-TiO₂ nanopowders with enhanced visible-light absorption,reduced bandgap and fast mobility of photogenerated carriers,and Ti⁴⁺was substituted in the TiO₂ lattice by cationic S⁶⁺and formed a new bond of Ti-O-S,and interstitially doped nitrogen atoms induced the formation of O-Ti-N bonds.The photocatalytic properties of A-SN-TiO₂ were tested for the reduction of Cr（Ⅵ） in water under both UV and visible light （λ>420 nm） irradiation in the absence of any sacrificial reagents,and compared with those of TiO₂,S-TiO₂,N-TiO₂ and B-SN-TiO₂ prepared with thiourea.The photocatalytic experiments indicated that A-SN-TiO₂ exhibit the highest photoreduction efficiency,and noticeably the photocatalytic reduction rate of Cr（Ⅵ） of A2-SN-TiO₂ was 100%under visible light irradiation after 60 min.Active species capture experiments and ESR showed that·O₂^- is the active radicals in the photocatalysis.Photocatalytic mechanism of A-SN-TiO₂ reduction of Cr（Ⅵ） was revealed based on the experimental results.更多还原