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采用溶胶-凝胶-原位碳热还原处理的方法,制备了一种含有氧空位(OV)的新型Zn掺杂β-Bi2O3纳米材料(OV-Zn∶Bi2O3),氧空位的浓度可以通过改变Zn2+的掺杂量进行调节.作为参照,只有氧空位没有Zn2+的新型β-Bi2O3(OV-β-Bi2O3)也通过类似的方法制得.通过紫外可见漫反射光谱、X射线光电子能谱、电子顺磁共振、光致发光光谱和光电化学测试,系统研究了氧空位和Zn2+掺杂对OV-Zn∶Bi2O3降解亚甲基蓝(MB)和2,4,6-三氯苯酚(2,4,6-TCP)可见光催化活性的综合影响.结果 表明,氧空位的引入不仅可以使光吸收向长波方向拓展,而且可以促进光生载流子的分离.因此,与传统的β-Bi2O3相比,OV-β-Bi2O3对亚甲基蓝(MB)和2,4,6-三氯苯酚(2,4,6-TCP)的降解活性显著增强.对于OV-Zn∶Bi2O3催化剂,Zn2+掺杂可使光催化剂的价带边缘向下移动,增强了光激发空穴的氧化能力,并且适量的锌掺杂也能提高光生载流子的分离效率.因此,OV-Zn∶Bi2O3的可见光活性优于OV-β-Bi2O3,而且当Zn与Bi物质的量之比为0.3时,OV-Zn∶Bi2O3-0.3对MB和2,4,6-TCP的降解活性最高.“,”A novel Zn-dopedβ-Bi2O3 nanomaterial (OV-Zn∶ Bi2O3) with two crystal defects,oxygen vacancy (OV)and doped Zn2+,was prepared via a sol-gel method followed by in-situ carbon thermal reduction treatment.The concentration of OV of OV-Zn ∶ Bi2O3 sample can be modulated by regulating the content of doped Zn2+.As a reference,the novel β-Bi2O3 having OV but without doped Zn2+ (OV-β-Bi2O3) was also synthesized via a similar process.The comprehensive effect of OV and doped Zn2+ on the visible-light-activity of OV-Zn ∶ Bi2O3 for the degradation of methylene blue (MB) and 2,4,6-trichlorophenol (2,4,6-TCP) was investigated by ultraviolet-visible light diffuse reflectance spectra,X-ray photoelectron spectra,electron spin resonance,photoluminescence spectrum and photoelectrochemical measurements.The results show that introduction of OV can not only drastically extend the photoabsorption into longer wavelength region but also promote the separation of photo-generated charge carriers.So,compared to traditional β-Bi2O3,OV-β-Bi2O3 demonstrated highly promoted activity for the degradation of methylene blue (MB)and 2,4,6-trichlorophenol (2,4,6-TCP).For OV-Zn ∶ Bi2O3 catalysts,Znic doping can make the valence band edge of catalysts move down and the oxidation ability of photo-excited holes increase.And appropriate amount of zinc doping can also improve the separation efficiency of photogenerated carriers.In contrast to OV-β-Bi2O3,the visible light activity of OV-Zn∶ Bi2O3 was further improved and OV-Zn ∶ Bi2O3-0.3 with a molar ratio (nZn/nBi) of 0.3 exhibited the highest activity for the degradation of MB and 2,4,6-TCP.