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以介孔SiO_2球为模板,TiCl_4为前躯体,制备了高催化活性的TiO_2纳米纤维以及非晶态合金(Ni-Mo-B)修饰的纳米纤维.TiO_2纳米纤维直径为7~10 nm,结晶度高,不仅对紫外光有很强的吸光度,而且对可见光也有一定程度的吸收.此外,纳米纤维降低了荧光强度,稳定了光生电子-空穴对.经过非晶态合金(Ni-Mo-B)修饰的纳米纤维进一步降低了荧光强度.在紫外光催化N_2与水合成氨的反应中,当反应时间为2 h时,P25氨氮产量为31μmol,Ti的转换频率(TOF)为0.5·h-1.纯TiO_2纳米纤维氨氮产量提高了约71%,达53μmol,Ti的转换频率(TOF)提高到了0.8·h-1.经过非晶态合金修饰的纳米纤维,氨氮产量达66μmol,Ti的转换频率(TOF)为0.95·h~(-1),比P25提高了113%.
TiO 2 nanofibers with high catalytic activity and Ni-Mo-B modified nanofibers were prepared by using mesoporous SiO 2 spheres as templates and TiCl 4 as precursors.The diameter of TiO 2 nanofibers was 7 ~ 10 nm, and the crystallization High degree, not only has a strong UV absorbance, but also to a certain extent, the visible light absorption.In addition, the nanofibers reduce the fluorescence intensity, stabilizing photogenerated electron-hole pairs.After the amorphous alloy (Ni-Mo- B) The modified nanofibers further reduce the fluorescence intensity.Under UV-light catalytic reaction of N 2 with ammonia, when the reaction time is 2 h, the output of P25 ammonia is 31μmol, the conversion frequency of Ti is 0.5 · h- 1. The yield of ammonia-nitrogen of pure TiO_2 nanofibers increased by 71%, reaching 53μmol, the conversion frequency of Ti (TOF) increased to 0.8 · h-1. After the amorphous alloy modified nanofibers, the yield of ammonia nitrogen reached 66μmol, the conversion of Ti The frequency (TOF) is 0.95 · h ~ (-1), which is 113% higher than that of P25.