氧化钛纳米管的水热法合成机理研究  

Mechanism of Hydrothermal Preparation of TiO_2 Nanotube

作　　者：王芹[1] 陶杰[1] 翁履谦[1] 徐国跃[1] 王秀华[1] 王函[1] 

机构地区：[1]南京航空航天大学材料科学与技术学院,南京210016

出　　处：《南京航空航天大学学报》2005年第1期130-134,共5页Journal of Nanjing University of Aeronautics & Astronautics

摘　　要：采用水热合成方法制备出外径约 8nm,壁厚为 1 nm的纳米管 ,以 TEM,XRD和 TG等分析手段对不同工艺条件下获得的产物进行了表征 ,对它们的热稳定性进行了测试。研究结果表明 ,纳米管是在 Na OH水热处理过程中形成的 ,而不是在清洗过程中形成的。其形成机理可能是纳米氧化钛颗粒在强碱作用下形成的 Na2 Ti O3片状物经过卷曲而成短纳米管 ,通过溶解 -吸收机理 ,逐渐长成长纳米管。但清洗溶液的 p H值对生成的纳米管的成分和结构有影响 ,通过控制清洗产物时的溶液的 p H值和热处理温度 ,可以获得组成分别为 Na2 Ti O3,H2 Ti O3和Ti O2 的纳米管 ,且纳米管具有较好的热稳定性 ,在 40 0℃下热处理后 ,能保持其纳米管形貌 ,60 0℃时 ,纳米管间有烧结的迹象 ,至 80Nanotubular titanates, with an external diameter of ar ou nd 8 nm and a wall thickness of about 1 nm, are prepared by hydrothermal proces sing, and the thermal stability is tested. The products are charactrized by tran smission electronic microscopy (TEM), X-ray diffraction (XRD) and thermogravime tric analysis (TGA). Experimental results indicate that the formation of nanotub ular products is due to hydrothermal treatment, rather than washing processes. H owever, pH values of washing solutions are used to determine the composition of products. Na 2TiO 3, H 2TiO 3and TiO 2nanotubes are synthesised by controlling the conditions of washing process and heat-treatmen t. The nanotubes may be formed from nanosheets through curling at the primary st age, and grew longer by dissulation-reprecipitation processing with the increas e of reaction time. The nanotubes remained on their shape at 400℃ are fused tog ether at 600℃. Finally, it completely losts their nanotubular shape to give the aggregated anatase nano-particles at 800℃.

关 键 词：二氧化钛纳米管 水热法 形成机理 热稳定性 

分 类 号：O614.411[理学—无机化学]