Zhu Wei, Wang Wenzhong, Shi Jianlin
State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, PR China.
J Phys Chem B. 2006 May 25;110(20):9785-90. doi: 10.1021/jp060305l.
A reverse cation-exchange approach for the synthesis of hollow PbSe nanospheres is successfully established. This route involves a new strategy of a stepwise, in-situ template-based evolution from spherical amorphous Se colloids to Se/Ag(2)Se core/shell colloids, then to hollow PbSe nanospheres. Se colloids are prepared as the initial product by utilizing the chelation of ethylenediamine to bulk Se. They are converted into Se/Ag(2)Se core/shell colloids through the reaction with Ag(+) in ethylene glycol. During the conversion from Ag(2)Se shell to PbSe shell, a small amount of tributylphosphine is crucial as the capping agent. The characterization results, including XRD, SEM, TEM, HRTEM, and EDX, reveal that hollow PbSe nanospheres with polycrystalline and cubic structure are prepared. The corresponding optical band gap is calculated to be 0.56 eV. This conformation is potentially beneficial to the improvement concerning the applications of PbSe nanostructures.
一种用于合成中空PbSe纳米球的反向阳离子交换方法成功建立。该路线涉及一种新策略，即从球形非晶态Se胶体逐步原位模板化演变为Se/Ag₂Se核壳胶体，再到中空PbSe纳米球。通过利用乙二胺与块状Se的螯合作用制备Se胶体作为初始产物。它们通过在乙二醇中与Ag⁺反应转化为Se/Ag₂Se核壳胶体。在从Ag₂Se壳向PbSe壳的转化过程中，少量三丁基膦作为封端剂至关重要。包括XRD、SEM、TEM、HRTEM和EDX在内的表征结果表明，制备出了具有多晶立方结构的中空PbSe纳米球。计算得出相应的光学带隙为0.56 eV。这种结构可能有利于改善PbSe纳米结构的应用。
