阵列型基底表面纳米球凸排布规律与SERS性能的关系

Relationship Between SERS Performance and Patterning Periodicity of Spherical Protrusion Array

采用程序旋涂、UV原位聚合和镀金等技术,将单分散SiO2微球在液态可聚合单体介质中快速剪切组装,高通量地简便制备球凸阵列型SERS基底。单片基底面积可达81 cm2,其表面为"长程球凸阵列、短程岛状分布"的等级制结构。以苯硫酚为探针的SERS结果表明,所得基底的Raman信号增强因子达107～108量级,且重现性良好(81 cm2范围内增强因子的相对标准偏差在16%～35%之间);改变组装介质的种类可以调控球凸的排布规律和排布密度,随着球凸排布密度和排布周期性的增加,基底Raman增强能力及其增强因子的重现性均有明显提高。

A facile and scalable fabrication method of Surface-enhanced Raman Scattering （SERS） active substrates with large area （81 cm2） has been achieved by means of programmed spin-coating, in situ polymerization and metallic deposition. The surface structure of the fabricated substrates is featured as a hierarchical structure of spherical protrusions array in long-range combine with island-like metallic film in short-range. The SERS performance of the obtained substrates has been explored using benzenethiol as the Raman probe. The SERS enhancement factors （EF） achieved in the order of 107 ~ l0s on average. The mean relative standard deviation （RSD） of EF was in the range of 16% to 35% over 4 x 81 cm2 which indicates the reproducibility of the substrates is excellent. The surface density and the patterning periodicity of spherical protrusions on the substrate surface can be modified by changing the type of precursor polymer monomers. Along with the surface density and the patterning periodicity of spherical protrusions increasing, both the Raman enhancement factor and the-reproducibility of the substrate definitely increase （the values of EF increase and the RSD of EF decreases, respectively）.