In this study ,real monodispersed ZnO spheres were prepared via a two-step method using diethyleneglycol as a milder reducing agent .T he diameter of as prepared ZnO spheres can be tuned from 100 nm to 350 nm precisely .The obtained ZnO spheres have narrow size distribution ,which permits their self-assembly to form photonic crystal .The effects of pre-cursor concentration and heating rate on the size and morphology of ZnO spheres were inves-tigated in detail .The results indicate that the key points of the method include the burst nu-cleation to form seeds at high temperature followed by rapid cooling to prevent agglomera-tion ,and proper precursor concentration as well as moderate grow th rate during the further growth process .Also ,the ZnO spheres was characterized by XRD ,SEM and TEM .Optical properties of the ZnO colloidal crystals were conducted by UV/visible/near-IR spectrum measurements .The redshift of photonic band gap is caused with increasing particle size .%通过两步法(也叫种子溶液方法)使用一缩二乙二醇(DEG)作为温和的还原剂制备出了单分散且粒径均一的氧化锌(ZnO)微球,所得微球尺寸分布窄,在100 nm到350 nm范围内,粒径大小可以精确控制.能够实现垂直自组装得到具有光子带隙的蛋白石光子晶体结构.讨论了温度、加热速率和前体浓度对ZnO微球粒径和结构的影响.结果表明:该方法的要点包括高温成核形成种子后的快速冷却以防止团聚,和生长过程中添加适量的上清液对增长速率的调控.采用XRD、SEM和T EM等对氧化锌微球的组成和微观结构进行了分析.通过紫外可见近红外光谱仪测试氧化锌薄膜的反射光谱,表明光子禁带随着胶体粒径的增大逐渐红移.
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