摘要
以[Bmim]Cl、[Bmim]BF4、[C2OH]mimCl和[C2OHmim]BF4四种室温离子液体为模板,采用微波加热前驱体Zn(OH)24-溶液的方法制备了多形貌纳米/微米ZnO。采用XRD、SEM、TEM对实验样品进行了结构和形貌表征,通过SEM照片分析了不同合成条件对产物形貌的影响。结果表明:合成产物为结晶良好,具有六方纤锌矿结构的ZnO;不同离子液体中合成了鳞状、片状、棒状、锥状纳米ZnO晶体单元,大量ZnO晶体聚集成微米球、花簇;随着前驱体原料配比增大,[0001]方向择优生长明显;随温度从80℃增加到95℃,ZnO纳米锥生长趋势总体趋于明显,长径比增大,同时产物形貌的规整性也明显变好;探讨了多形貌纳米/微米ZnO的生长机理;采用室温下光致发光(PL)光谱对多形貌纳米ZnO的光学性能研究表明,多形貌纳米ZnO具有较强的紫外发射和相对较弱的蓝绿发射,离子液体[Bmim]Cl中合成的ZnO纳米锥在387nm处紫外发射峰强度最大,离子液体[C2OHmim]Cl中合成的ZnO纳米片在497nm处有较强的绿光发射峰。
Using room temperature ionic liquids（RTILs）[Bmim]Cl,[Bmim]BF4,[C2OH]mimCl and [C2OHmim]BF4 as template,zinc oxide of different morphology was successfully synthesized with microwave method in Zn（OH）2-4 precursor solution.The as-prepared samples were characterized by X-ray diffraction（XRD）,scanning electron microscopy（SEM）,transmission electron microscopy（TEM）.The influence of different conditions on the morphology were also studied by SEM.The results showed that the nanometer ZnO were single crystalline with the wurtzite structure.ZnO nanoflakies,nanosheets,nanorods,nanocones,micro spherical and micro flowers were prepared with different RTILs.Preferential growth orientation along the [0001] direction became more apparent with the increasing of raw materials ratio.ZnO nanocones tend to be uniform,the crystallization is gradually improved and the length-diameter ratio is slowly raised with the temperature increasing from 80 ℃ to 95 ℃.A possible growth mechanism was also proposed to account for the formation of the multi-morphology ZnO.The photoluminescence spectra of the multi-morphology ZnO were studied at room temperature.The spectra show the sample which were prepared using RTILs as template emitted strong ultra violet emissions and relatively weak defect emissions.ZnO nanocones prepared with [Bmim]Cl as template emitted the most strong ultra violet emission peak at 387 nm.ZnO nanosheets prepared with [C2OHmim]Cl as template generated the sharp strong green light emission peak at 387 nm.
出处
《硅酸盐通报》
CAS
CSCD
北大核心
2009年第6期1340-1346,共7页
Bulletin of the Chinese Ceramic Society
基金
江西省省教育厅科技项目(GJJ08296)
