SERS

Surface Enhanced Raman Spectroscopy

Raman spectroscopy is based on scattering processes that are intrinsically weak when compared to optical processes such as absorption and fluorescence; therefore, it requires an amplification of the signal. Approximately only 1 in 10⁷ photons are inelastically scattered.

Enhancement is required to provide sufficient signal from these excitations, and the vibrations they correspond to, in order to gain adequate sensitivity in order to observe adsorbed species at electrode interfaces. Signal enhancements can be achieved via surface-enhanced Raman spectroscopy (SERS) where the strong Raman signal enhancement occurs via the excitation of a localised surface plasmon on metallic nanostructures by an external oscillating electric field that matches the resonant frequency of the plasmon. To study battery interfacial reactions, amplification is achieved with nanostructured gold or silver electrodes, and the enhancement is highly dependent on the size and morphology of the layer. This allows enhancement of the Raman signal of interfacial species in close proximity of the nanoscale-roughened electrode.

Publications, review articles and book chapters on SERS

Trapped interfacial redox introduces reversibility in the oxygen reduction reaction in a non-aqueous Ca²⁺ electrolyte
Y.-T. Lu, A.R. Neale, C.-C. Hu, L.J. Hardwick
Chem. Sci., 1 (2021) 8909 DOI

Advanced spectroelectrochemical techniques to study electrode interfaces within lithium-ion and lithium-oxygen batteries 
A. J. Cowan and L. J. Hardwick
Annu. Rev. Anal. Chem., 12 (2019), 23.1- 23.24 DOI

Metal-Air Batteries: Fundamentals and Applications; Chapter 9 Metal-Air Battery: In Situ Spectro-electrochemical Techniques
I. M. Aldous, L. J. Hardwick, R. J. Nichols, and J. Padmanabhan Vivek
Ed. Xin-bo Zhang
Wiley 2018, Book

Time-resolved SERS study of the Oxygen Reduction Reaction in Ionic Liquid Electrolytes for Non-Aqueous Lithium-Oxygen Cells
P. Radjenovic, L.J. Hardwick
Faraday Discuss., 206 (2018) 379-392 DOI

Analytical SERS: General Discussion
H. Aitchison,  J. Aizpurua,  H. Arnolds,  J. Baumberg,  S. Bell,  A. Bonifacio,  R. Chikkaraddy,  P. Dawson,  B. de Nijs,  V. Deckert,  I. Delfino,  G. Di Martino,  O. Eremina,  K. Faulds,  A. Fountain,  S. Gawinkowski,  M. Gomez Castano,  R. Goodacre,  J. Gracie,  D. Graham,  J. Guicheteau,  L. Hardwick,  M. Hardy,  C. Heck,  L. Jamieson,  M. Kamp,  A. Keeler,  C. Kuttner,  J. Langer,  S. Mahajan,  N. M. Sabanés,  K. Murakoshi,  M. Porter,  G. Schatz,  S. Schlücker,  Z. Tian,  A. Tripathi,  R. Van Duyne  and  P. Vikesland  
Faraday Discuss., 205 (2017), 561- 600 DOI

Solvent-Mediated Control of the Electrochemical Discharge Products of Non-Aqueous Sodium-Oxygen Electrochemistry
I.M. Aldous, L.J. Hardwick
Angew. Chem. Int. Ed., 55 (2016) 8254-8257 DOI  

Utilizing In Situ Electrochemical SHINERS for Oxygen Reduction Reaction Studies in Aprotic Electrolytes 
T. Galloway, L.J. Hardwick
J. Phys. Chem. Lett., 7 (2016) 2119-2124 DOI  

Influence of Tetraalkylammonium Cation Chain Length on Gold and Glassy Carbon Electrode Interfaces for Alkali Metal–Oxygen Batteries
I.M. Aldous, L.J. Hardwick
J. Phys. Chem. Lett., 5 (2014) 3924–3930 DOI PDF ACS LiveSlides^TM