交流电沉积原位制备Au/Cu双金属SERS探测器

摘要

为进一步提高拉曼探测器的检测灵敏度、降低制备成本,使用交流电沉积法在预定的微区域内制备Au/Cu双金属纳米枝晶作为表面增强拉曼散射(surface-enhanced Raman scattering,SERS)基底.通过调节电解液中金、铜离子的浓度配比,制备不同金、铜质量比的SERS基底.以四巯基吡啶作为指针分子,进行激光共焦显微拉曼实验.结果表明:Au/Cu双金属纳米枝晶性能优于单独Au纳米枝晶与Cu纳米枝晶,且铜质量占比为30.1％的双金属SERS基底相比质量占比为13.2％、44.3％的基底具有更高的拉曼活性.从物理增强机理的角度,揭示增强性能与形貌特征的关系,即纳米枝晶分支分布越密集,性能越好.%In order to improve the detection sensitivity and reduce the preparation cost of Raman detector,Au/Cu bimetallic nano-dendrites are prepared as the surface-enhanced Raman scattering(SERS)substrates in a predetermined micro-area using AC electrodeposition.SERS substrates with different gold and copper mass ratios are prepared by adjusting the concentration of gold and copper ions in the electrolyte.4-mercaptopyridine is taken as the pointer moleculars to have a laser confocal microscopy Raman experiment.Results show that performance of Au/Cu bimetallic nano-dendrites is better than Au nanocrystalline dendrites or Cu nanocrystalline dendrites.In detail,SERS substrates with mass ratio of 30.1％copper exhibit better Raman activity than that with a copper mass ratio of 13.2％and 44.3％.The relationship between the enhanced performance and the morphology is revealed from the physical enhancement mechanism,which show that,denser the branch distribution of the nano dendrites is,better enhancing performance will be.