【摘要】 利用化学方法在常温下成功地制备了ZnO胶体,颗粒尺寸在5nm以下,其量子限域效应十分明显。通过跟踪测试样品的吸收谱,估价了带边吸收与胶体颗粒大小的关系,并研究了随着胶体颗粒的长大,可见发射强度的变化。通过添加表面活性剂,使粒子的表面得到修饰,从而增强了紫外发射。同时对可见发射机制进行了探讨,指出绿带发射至少部分是来自表面浅陷阱(如单离子氧空位)电子到深陷阱空穴的跃迁。更多还原

【Abstract】 ZnO colloids were prepared at room temperature by chemical method. The mean size of the particles was less than 5 nm and the quantum confinement effect was very appreciable. The absorption band edge on the size of the particles was given by measuring the absorption spectrum of ZnO colloids as the reaction time was increased. The visible emission intensity was also studied as the size of the particles was increased. By adding surfactant to the ZnO colloidal solution, the UV emission was increased due to the surface modification. The mechanism behind the visible luminescence was discussed and attributed to the transition from the shallower surface trapped electrons to the inner deeper trapped holes.更多还原