Wang Rongming, Yang Wantai, Song Yuanjun, Shen Xiaomiao, Wang Junmei, Zhong Xiaodi, Li Shuai, Song Yujun
Department of Physics, School of Mathematics and Physics, University of Science &Technology Beijing, Beijing 100083, China.
College of Materials and Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
Sci Rep. 2015 Mar 30;5:9189. doi: 10.1038/srep09189.
A new methodology based on core alloying and shell gradient-doping are developed for the synthesis of nanohybrids, realized by coupled competitive reactions, or sequenced reducing-nucleation and co-precipitation reaction of mixed metal salts in a microfluidic and batch-cooling process. The latent time of nucleation and the growth of nanohybrids can be well controlled due to the formation of controllable intermediates in the coupled competitive reactions. Thus, spatiotemporal-resolved synthesis can be realized by the hybrid process, which enables us to investigate nanohybrid formation at each stage through their solution color changes and TEM images. By adjusting the bi-channel solvents and kinetic parameters of each stage, the primary components of alloyed cores and the second components of transition metal doping ZnO or Al2O3 as surface coatings can be successively formed. The core alloying and shell gradient-doping strategy can efficiently eliminate the crystal lattice mismatch in different components. Consequently, varieties of gradient core-shell nanohybrids can be synthesized using CoM, FeM, AuM, AgM (M = Zn or Al) alloys as cores and transition metal gradient-doping ZnO or Al2O3 as shells, endowing these nanohybrids with unique magnetic and optical properties (e.g., high temperature ferromagnetic property and enhanced blue emission).
基于核心合金化和壳层梯度掺杂开发了一种新方法，用于合成纳米杂化物，该方法通过耦合竞争反应，或在微流控和间歇冷却过程中混合金属盐的顺序还原成核和共沉淀反应来实现。由于在耦合竞争反应中形成了可控的中间体，纳米杂化物的成核潜伏时间和生长可以得到很好的控制。因此，通过混合过程可以实现时空分辨合成，这使我们能够通过溶液颜色变化和透射电子显微镜图像研究纳米杂化物在每个阶段的形成。通过调整每个阶段的双通道溶剂和动力学参数，可以依次形成合金化核心的主要成分和过渡金属掺杂ZnO或Al2O3作为表面涂层的次要成分。核心合金化和壳层梯度掺杂策略可以有效消除不同成分中的晶格失配。因此，可以使用CoM、FeM、AuM、AgM（M = Zn或Al）合金作为核心，过渡金属梯度掺杂ZnO或Al2O3作为壳层来合成各种梯度核壳纳米杂化物，赋予这些纳米杂化物独特的磁性和光学性质（例如，高温铁磁性和增强的蓝光发射）。
