低温水热制备ZnO纳米棒及其生长机理

以Zn(NO3)2·6H2O为前驱体,在碱性环境中,低温水热方法直接制备了ZnO纳米棒.应用场发射扫描电子显微镜(FESEM)、能谱仪(EDS)和X射线衍射仪(XRD)对样品进行了表征；通过光催化降解亚甲基蓝来评价ZnO的光催化活性；对60℃,1～24 h范围内不同水热样品,进行了形貌观察,分析了ZnO的形核过程.结果表明:ZnO为六边棱柱状纳米棒,晶型为纤锌矿结构；ZnO纳米棒的表观生长速率约为0.7μm/h,表观形核时间约为3 min;碱性条件是影响形核的重要因素；光催化活性随水热时间的增加而增强.

Synthesis and Growth Mechanism of ZnO Nanorods by Hydrothermal Method at Low Temperatures

ZnO nanorods were directly synthesized by hydrothermal method at low temperatures with Zn(NO3)2·6H2O as precursor in basic solution.The structures were characterized by X-ray diffraction(XRD),energy disperse spectroscopy(EDS) and field emission scanning electron microscopy(FESEM).The photocatalytic activity was evaluated via photocatalytic degradation of methylene blue.The nucleation processes were analyzed by studying morphology characterizations of samples synthesized by different hydrothermal time at 60 ℃.The results show that the as-prepared ZnO is hexagonal prism nanorod and the crystal form is wurtzite;the apparent growth rate of ZnO nanorods is 0.7 μm/h,the apparent nucleation time is 3 min;basic solution plays an important role in nucleation processes;the photocatalytic activity increases with the increase of hydrothermal time.