Ellis R. Lippincott Award: SERS studies for the last 30 years in the Ozaki group at Kwansei Gakuin University

In fifteen words or less, explain the significance of this contribution (Novel Aspect).: To learn milestones in the SERS studies at Ozaki group for the last 30 years.

Abstract Text:

Let us review milestones of the SERS studies at the Ozaki group in Kwansei Gakuin University for the last 30 years.   

In 2008  Ozaki and Tamitake Itoh, designed a novel SERS experimental system that enabled them to perform electron microscope measurement, plasmon resonance measurement, and SERS measurement for the same single nano particle dimer. They could elucidate the relation among the shape of a silver nanoparticle dimer, plasmon resonance and SERS just for the same single nano particle dimer. Based on the experimental results they reproduced SERS cross section.  Comparison of the experimental SERS spectra with the calculated SERS spectra allows them to reach quantitative verification of electromagnetic enhancement effect.

 Ozaki worked with Wei Ji on the mechanism and application of semiconductor-enhanced Raman scattering. Their study on semiconductor SERS revealed that Mie resonances scattered near-field effect provided a coherence framework for modeling the electromagnetic mechanism of SERS on semiconductors (W. Ji et al. Angew. Chem. Int. Ed. 58, 14452, 2019).

Ozaki et al. carried out 3D SERS imaging of polymer layers using chemically synthesized highly symmetric nanoporous silver microparticles (S. Vantasin et al. Angew. Chem. Int. Ed.,55, 8391(2016)). reaction.

Ozaki et al. first demonstrated the application of CT-SERS for the enantiomeric discrimination of various chiral alcohols (Y. Wang et al. Angew. Chem., Int. Ed. 53, 13866 (2014)). The “chiral probe” in this work is the N atom arranged in self-assembled monolayers of 4-mercaptopyridine (4-MPy) on Ag NPs. The S and R enantiomer-4-MPy complexes may differ in their energy states, owing to the difference in their stereochemistry, which influences the CT transitions. This slight difference in the CT transitions will increase with the resonant excitation of the enantiomer complexes, leading to the selective enhancement of the nontotally symmetric mode in the SERS spectra of 4-MPy.

Ozaki et al. designed a chemically modified TERS tip for liquid TERS (P. Pienpinijtham et al., Nanoscale, 14, 5265, 2022). Using this tip, they carried out nanoscale quantitative measurement of pH profile at a solid-liquid interface. They also demonstrated the discrimination between enantiomers by TERS using a chemically modified TERS tip.