不同粒径、超均匀球形金纳米粒子合成及其表面增强拉曼散射效应研究

发布时间：2018-08-16 17:29

【摘要】：以氯金酸为原料,抗坏血酸为还原剂,柠檬酸钠为保护剂,用化学还原(种子生长)法制备了不同粒径、超均匀的球形金纳米粒子溶胶,并通过紫外可见吸收光谱(UV-Vis)和扫描电子显微镜(SEM)进行表征。结果表明,随着金纳米粒子粒径的增大,其UV-Vis光谱中的吸收峰发生红移并出现四极峰。为进一步研究金纳米粒子表面增强拉曼散射(SERS)效应的作用机理并优化其灵敏度,我们以罗丹明6G(R6G)为探针分子,对不同粒径的金纳米粒子进行SERS表征,发现R6G的SERS信号随着金纳米粒子的增大先增强后减弱。当金纳米粒子的平均粒径达到120nm时,产生最强SERS信号增强,增强因子约为1.1×10~7。三维时域有限差分法(3D-FDTD)理论模拟纳米粒子阵列电磁场分布结果与实验数据的趋势一致。
[Abstract]:Spherical gold nanoparticles were prepared by chemical reduction (seed growth) method using chlorgold acid as raw material ascorbic acid as reducing agent and sodium citrate as protective agent. It was characterized by UV-vis absorption spectrum (UV-Vis) and scanning electron microscope (SEM). The results show that with the increase of the particle size of gold nanoparticles, the absorption peaks in the UV-Vis spectra shift red and the quadrupole peaks appear. In order to further study the mechanism of surface enhanced Raman scattering (SERS) effect of gold nanoparticles and optimize their sensitivity, Rhodamine 6G (R6G) was used as probe molecule to characterize gold nanoparticles with different particle sizes by SERS. It is found that the SERS signal of R6G increases first and then weakens with the increase of gold nanoparticles. When the average particle size of gold nanoparticles reaches 120nm, the strongest SERS signal is produced, and the enhancement factor is about 1.1 脳 10 ~ (7). Three dimensional finite difference time domain (3D-FDTD) theory is used to simulate the electromagnetic field distribution of nanoparticles array, which is consistent with the experimental data.
【作者单位】：江西理工大学应用科学学院矿冶工程系;浙江中烟工业有限责任公司技术中心;厦门大学化学化工学院;
【基金】：国家自然科学基金项目(21473140)资助
【分类号】：O657.37

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