School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
Nanoscale. 2013 Oct 21;5(20):9598-603. doi: 10.1039/c3nr02896h.
This study investigates the feasibility of loading nanostructured lasing medium and magnetic nanocrystals in the same microbead for potential applications in bio- and chemical sensing. A sequential infiltration process is proposed and tested for the preparation of magnetic and lasing microbeads by incorporating, respectively, iron oxide nanocrystals in the inner cores and colloidal quantum dots (CQDs) in the periphery regions of mesoporous silica microbeads. The co-doped bead structure was confirmed by electron microscopy and energy dispersive spectroscopy. The lasing action of the CQD gain medium in the mesoporous beads was characterized with micro-photoluminescence, revealing sharp whispering gallery mode lasing signatures, whereas the distinguishing superparamagnetic property was measured from the co-doped microbeads with vibrating sample magnetometry.
本研究旨在探索将纳米结构激光介质和磁性纳米晶体装载到同一微球中的可行性，以期在生物和化学传感领域得到应用。提出并测试了一种顺序渗透工艺，用于制备磁性和激光微球，分别将氧化铁纳米晶体掺入介孔硅微球的内芯和胶体量子点（CQD）掺入其外围区域。通过电子显微镜和能量色散光谱证实了共掺杂珠结构。通过微光致发光对介孔珠中 CQD 增益介质的激光作用进行了表征，显示出尖锐的 whispering gallery 模式激光特征，而通过振动样品磁强计从共掺杂微球中测量到了独特的超顺磁性。
