以介孔碳为模板,成功合成了具有较大比表面积的多孔TiO2,并研究了煅烧时间对所获材料结构及电化学性能的影响.采用X射线粉末衍射、场发射扫描电镜、高分辨透射电镜、氮气吸附-脱附实验和电化学测试对合成的材料进行了表征.测试结果表明所合成的材料是由很小的纳米颗粒组成,表面积大,孔分布窄.经500℃热处理2h的样品为锐钛矿型,继续延长热处理时间至12h,所得样品出现了金红石相,且12h所得材料的初始容量高于2h所得样品,这可能和样品的结晶度有关.
A kind of nanostructure TiO2 with large surface area was synthesized successfully by using mesoporous carbon as sacrificial template. The effects of annealing time on the morphologies and electrochemical performances of the as-prepared samples were studied. The as-prepared material was characterized by X-ray diffraction (XRD), Field emission scanning electron microscope (FESEM), High-resolution transmission electron microscope (HRTEM), Nitrogen adsorption and desorption experiments and electrochemical measurements systematically. The results show that the as-synthesized TiO2 is composed of nanoparticles, which has a narrow porous distribution with high specific surface area. It is also found that the sample synthesized at 500℃ for 2 h is pure anatase TiO2, when the sintering time is prolonged to 12 h, there is a trace amount of futile phase coexisted with the anatase phase. However, the sample sintered for 12 h exhibits higher initial capacity than that of the sample sintered for 2 h, which may be caused by different crystallization of samples.