SERS Studies Of Explosive Molecules With Diverse Copper Nanostructures Fabricated Using Ultrafast Laser Ablation

¹School of Physics, University of Hyderabad, Prof. C.R. Rao Road, Gachibowli, Hyderabad 500046, India

²Advanced Center of Research in High Energy Materials (ACRHEM), University of Hyderabad, Prof. C.R. Rao Road, Gachibowli, Hyderabad 500046, India

³National Institute of Technology Andhra Pradesh, Tadepalligudem, Andhra Pradesh 534101, India

Adv. Mater. Lett., 2015, 6 (12), pp 1073-1080

DOI: 10.5185/amlett.2015.6007

Publication Date (Web): Nov 24, 2015

Copyright © IAAM-VBRI Press

E-mail: soma_venu@uohyd.ac.in

Abstract

We report the fabrication and application of ultra-short pulse laser induced nanostructures (NSs) on copper surface accomplished with different pulse energies and number of pulses. The shapes and sizes of NSs have been evaluated from the field emission scanning electron microscopy (FESEM) data which illustrated different ablation mechanisms in picosecond (ps) and femtosecond (fs) domains. The Cu NSs generated with ps pulses demonstrated Raman enhancements upto ~10⁵-10⁸ in the case of the explosive molecules of 1,1-diamino-2,2-dinitroethene (FOX-7), 5 Amino, 3-nitro,1,3,5-nitrozole (ANTA) and 2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20). The SERS studies were repeated two more times on the same substrate following a simple cleaning procedure.  We achieved considerable enhancement factors (of >10⁵) for the Raman modes of an explosive molecule of FOX-7 on fs laser fabricated Cu NSs.

Keywords

Laser ablation, picosecond, femtosecond, explosives detection, SERS.