Liang Yuan-Chang, Xu Nian-Cih, Wang Chein-Chung, Wei Da-Hua
Institute of Materials Engineering, National Taiwan Ocean University, Keelung 20224, Taiwan.
Graduate Institute of Manufacturing Technology and Department of Mechanical Engineering, National Taipei University of Technology, Taipei 10608, Taiwan.
Materials (Basel). 2017 Jul 10;10(7):778. doi: 10.3390/ma10070778.
TiO₂-CdO composite rods were synthesized through a hydrothermal method and sputtering thin-film deposition. The hydrothermally derived TiO₂ rods exhibited a rectangular cross-sectional crystal feature with a smooth surface, and the as-synthesized CdO thin film exhibited a rounded granular surface feature. Structural analyses revealed that the CdO thin film sputtered onto the surfaces of the TiO₂ rods formed a discontinuous shell layer comprising many island-like CdO crystallites. The TiO₂-CdO composite rods were highly crystalline, and their surfaces were rugged. A comparison of the NO₂ gas-sensing properties of the CdO thin film, TiO₂ rods, and TiO₂-CdO composite rods revealed that the composite rods exhibited superior gas-sensing responses to NO₂ gas than did the CdO thin film and TiO rods, which can be attributed to the microstructural differences and the formation of heterojunctions between the TiO₂ core and CdO crystallites.
通过水热法和溅射薄膜沉积法合成了TiO₂-CdO复合棒。水热法制备的TiO₂棒呈现出具有光滑表面的矩形横截面晶体特征，而合成的CdO薄膜呈现出圆形颗粒表面特征。结构分析表明，溅射在TiO₂棒表面的CdO薄膜形成了一个由许多岛状CdO微晶组成的不连续壳层。TiO₂-CdO复合棒具有高度结晶性，其表面粗糙。对CdO薄膜、TiO₂棒和TiO₂-CdO复合棒的NO₂气敏性能进行比较，结果表明，复合棒对NO₂气体的气敏响应优于CdO薄膜和TiO棒，这可归因于微观结构差异以及TiO₂核与CdO微晶之间形成的异质结。
