Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, China.
Nanoscale. 2014 Jun 7;6(11):5971-9. doi: 10.1039/c4nr00975d. Epub 2014 Apr 29.
Herein, we demonstrate the design and fabrication of multifunctional triplex Fe3O4@TiO2@Au core-shell magnetic microspheres (MSs), which show excellent surface enhanced Raman scattering (SERS) activity with high reproducibility and stability. In addition, due to their excellent catalytic properties, the as-prepared Fe3O4@TiO2@Au magnetic MSs can clean themselves by photocatalytic degradation of target molecules adsorbed onto the substrate under irradiation with visible light, and can be re-used for several cycles with convenient magnetic separability. The influence of the size and distribution of Au nanoparticles (NPs) on the Fe3O4@TiO2 beads is investigated. The optimized samples employing Au NPs of 15 nm size and an areal density of about 2120 Au NPs on every MS show the best SERS activity and recyclable performance. The experimental results show that these magnetic MSs indicate a new route in eliminating the 'single-use' problem of traditional SERS substrates and exhibit their applicability as analytical tools for the detection of different molecular species.
在此，我们展示了多功能三联 Fe3O4@TiO2@Au 核壳磁性微球 (MSs) 的设计和制造，其具有出色的表面增强拉曼散射 (SERS) 活性，重现性和稳定性高。此外，由于其优异的催化性能，所制备的 Fe3O4@TiO2@Au 磁性 MSs 可以通过可见光照射下吸附在基底上的目标分子的光催化降解来自我清洁，并通过方便的磁性分离可重复使用几个循环。研究了 Au 纳米颗粒 (NPs) 的尺寸和分布对 Fe3O4@TiO2 珠的影响。采用尺寸为 15nm 的 Au NPs 和每个 MS 上约 2120 个 Au NPs 的面密度的优化样品表现出最佳的 SERS 活性和可重复使用性能。实验结果表明，这些磁性 MSs 为消除传统 SERS 基底的“一次性”问题开辟了新途径，并表现出作为用于检测不同分子种类的分析工具的适用性。
