Surface-enhanced Raman scattering (SERS) has opened up a wide research field both in the physics and chemistry of interfaces. It has become an increasingly popular technique not only for studying the vibrational signatures of molecules or ions at trace concentrations but also in estimating their possible orientations on the nanometallic surfaces. Since the pioneering work reported by Fleischmann et al., SERS has been a subject of extensive theoretical and experimental investigations. It provides the high information content of vibrational spectroscopy (yielding a molecular “fingerprint”) while demonstrating detection limit down to the single-molecule level. In fact, SERS spectra are recorded in the far field which is primarily controlled by the near field architecture of the plasmonic substrates and far field characteristics of non-plasmonic dielectric substrates. The physics behind the phenomenon still remains a matter of controversy, though it is now widely accepted that there are two main contributions (Electromagnetic Mechanism (EM) and Charge Transfer (CT)) to the overall effect.
The recent upthrust in the field of SERS theory and its applications are mainly focused in three directions: i) Fabrication of novel SERS active substrates; ii) Understanding the mechanisms involved in the SERS phenomenon; iii) Use of SERS for imaging and the search for new applications.
The degree in enhancements of SERS signal is strongly dependent on the interaction between adsorbed molecules and the surface of plasmonic novel metal nanostructures. Over the last 30 years, researchers tried to optimize the substrates structure and configuration to maximize enhancement factors. Recently efforts have been made to identify new plasmonic metal and non-plasmonic dielectric, as well as different shapes that support increased SERS enhancement. The choice of appropriate substrate in terms of its structure and configuration along with the excitation source are important to ensure maximum signal generation and enhancement. The remarkable analytical sensitivity of SERS has yet to be translated into the development of widely accepted Fibre-Optical SERS, Tip Enhanced Raman Scattering, Single Molecule Detection Using SERS, SERS of Molecules adsorbed in Langmuir-Blodgett (LB) Film, diagnostic applications etc., mainly because of the difficulty in preparing robust and correct surface morphologies that provide maximum SERS enhancements.
In this Research Topic, we welcome Original Research, Review, Mini Review and Perspective articles on themes including, but not limited to:
• SERS study of organic bio-molecules adsorbed by metallic nanocolloids aided by ab-initio, DFT and CPMD
• Preparation and characterisation of ordered plasmonic and non-plasmonic SERS active substrates using LB and other soft lithographic techniques
• Study of various EM and CT mechanisms involved in the phenomena of SERS
• Effects of surface topography on SERS response
• Various theoretical modelling techniques on nano-clusters adsorbed by molecules and its compression with experimental observations
• Study of SERS in various applications from detection up to the limit of single molecule to diagnosis in medical science
• Expanding applications of SERS through versatile nanomaterials engineering
We would like to acknowledge
Dr Subhendu Chandra, who has acted as a coordinator and has contributed to the preparation of the proposal for this Research Topic.