Affiliation:
1. Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China
2. Shenzhen Engineering Research Center for High Resolution Light Field Display and Technology, Southern University of Science and Technology, Shenzhen 518055, China
Abstract
We demonstrated a low-cost, highly sensitive hybrid Ag-Cu substrate with enhanced absorption for the excitation laser beam via the nanosphere lithography technique. The hybrid Ag-Cu surface-enhanced Raman spectroscopy (SERS) substrate consists of a Cu nanoarray covered with Ag nanoparticles. The geometry of the deposited Cu nanoarray is precisely determined through a self-assembly nanosphere etching process, resulting in optimized absorption for the excitation laser beam. Further Raman enhancement is achieved by incorporating plasmonic hotspots formed by dense Ag nanoparticles, grown by immersing the prepared Cu nanoarray in a silver nitrate solution. The structural design enables analytical enhancement factor of hybrid Ag-Cu SERS substrates of 1.13 × 105. The Ag-Cu SERS substrates exhibit a highly sensitive and reproducible SERS activity, with a low detection limit of 10−13 M for Rhodamine 6G detection and 10−9 M for 4,4′-Bipyridine. Our strategy could pave an effective and promising approach for SERS-based rapid detection in biosensors, environmental monitoring and food safety.
Funder
National Key R&D Program of China
National Natural Science Foundation of China
Guangdong Innovative and Entrepreneurial Research Team Program
Shenzhen Science and Technology Innovation Commission
Shenzhen Development and Reform Commission
Key Lab of Modern Optical Technologies of Education Ministry of China, Soochow University
Subject
Clinical Biochemistry,General Medicine,Analytical Chemistry,Biotechnology,Instrumentation,Biomedical Engineering,Engineering (miscellaneous)