Facility Agriculture: Development of Green Power FacilityDepartment of Materials Science Engineering / Song, Jenn-Ming / Professor
設施農業:綠能設施開發【材料科學與工程學系宋振銘教授】

論文篇名 Magnetically-controllable Hollow Multi-shell Magnetite Spheres as Stable and Reusable SERS Substrates
期刊名稱 APPLIED SURFACE SCIENCE
發表年份,卷數,起迄頁數 2021,536,147705
作者 Huang, Yu-Fang; Huang, Wen-Chi; Hsu, Pei-Kai; Song, Jenn-Ming(宋振銘)*; Gloter, Alexandre; Chen, Shih-Yun*
DOI 10.1016/j.apsusc.2020.147705
中文摘要 本研究成功合成Ag@SiO2@Fe3O4中空複合球作為具磁控與可回收功能可懸浮SERS基板之用。中空球內殼為厚15-30nm、以噴霧裂解法製備之強鐵磁Fe3O4,披覆可保護Fe3O4之SiO2外殼層,最表面則散佈有可提供局部表面共振電漿之奈米銀粒。裸Fe3O4中空球之矯頑磁場(Hc)與飽和磁化強度(Ms)分別高達200 Oe及130 emu/g,Ms超越文獻值30%以上。與實心複合球相較,本研究開發之中空複合球因可懸浮、能與更多帶測物反應的特質,SERS訊號強化至2.6倍。外加以磁場收集複合中空球可進一步增強訊號1.5倍。本研究亦證實複合中空球使用於SERS量測之重覆使用可行性。
英文摘要 This study successfully synthesized magnetically-manipulatable and reusable SERS active buoyant substrates, i.e. Ag@SiO2@Fe3O4 composite hollow spheres. The composites comprised mesoscopic hollow spheres with a Fe3O4 inner shell of 15-30 nm in thickness and strong ferromagnetism, which were synthesized using spray pyrolysis and the subsequent reduction, and a SiO2 outer shell to maintain the stability of Fe3O4, as well as Ag nanoparticles on the sphere surface providing localized surface plasmon resonance. The coercive field (Hc) of bare Fe3O4 hollow sphere reached 200 Oe, and the saturation magnetization (Ms) was 130 emu/g at 300 K, which was at least 30% higher than the reported values no matter in bulk or nanoscales.  Compared to composite spheres with Fe3O4 solid cores, the SERS signal intensity of hollow structures was 2.6 times greater, which could be attributed to the buoyancy of hollow structure which contribute to more interaction with the target analytes. Under external magnetic field, these ferromagnetic hollow composites can be concentrated and separated easily, resulting in a more augmented SERS effect (about 1.5 times higher than those collected without applying magnetic field). This study also demonstrated the possibility to reuse those composites for SERS measurements.