掺铁二氧化钛纳米线的合成及其光催化性能

Synthesis of TiO_2 Nanowires Doped with Fe^(3+) and Their Photocatalytic Activities

首次以钛酸丁酯、异丙醇等有机物为原料,在10M NaOH溶液中水解后,于180℃水热24h,一步法合成二氧化钛纳米线(TNWs),并用扫描电子显微镜(SEM)和X射线衍射(XRD)等手段表征其形貌和结构。结果表明,所得TNWs焙烧到950℃时,仍为锐钛矿相,表明本制备方法迟滞了二氧化钛由锐钛矿相到金红石相的转变。此外,以甲基橙为目标降解物,在300 W汞灯照射下,研究了不同水热温度、保温时间及掺杂量对掺铁二氧化钛纳米线(Fe-TNWs)光催化性能的影响。结果表明,于750℃焙烧4h制备的掺铁摩尔百分数为0.5%的TNWs,具有最强的光催化降解性能,其降解速率和效率较未掺杂的样品都有了大幅度的提高。

Titanium dioxide nanowires（TNWs） were synthesized by one-step hydrothermal method,using tetrabutyl titanate,isopropanol and sodium hydroxide（10 M） as raw materials and reacting at 180℃ for 24 h for the first time.The as-synthesized TNWs were characterized by scanning electron microscopy（SEM） and X-ray diffractometry（XRD）.The results show that the as-prepared nanowires are still anatase even if the calcination temperature increased to 950℃,indicating the delayed phase transition of TiO2 from anatase to rutile.In addition,the effect of calcination temperature,calcination time and the doping amount of Fe on the photocatalytic activity of the TNWs were studied,by using methyl orange solution as the target degradation material and 300 W UV-lamp as light source.It is found that the nanowires doped with Fe of 0.5 at.% and then calcinated at 750℃ for 4 h have the optimum photocatalytic activity.And their corresponding degradation rate and ratio are larger than the ones without doping.