TY - JOUR

T1 - Surface-Tip-enhanced Raman Scattering by CdSe Nanocrystals on Plasmonic Substrates

AU - Milekhin, Ilya A.

AU - Milekhin, Alexander G.

AU - Zahn, Dietrich R.T.

N1 - Funding Information: and Germany (A115807), DFG project (ZA 146/43–1), DFG project (ZA 146/44-1), the Russian Science Foundation (Project identifier: 22-12-00302). Funding Information: Funding: The authors gratefully acknowledge financial support from Volkswagen Foundation Trilateral Partnerships – Cooperation Projects between Scholars and Scientists from Ukraine, Russia, Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland.

PY - 2022/7/1

Y1 - 2022/7/1

N2 - This work presents an overview of the latest results and new data on the optical response from spherical CdSe nanocrystals (NCs) obtained using surface-enhanced Raman scattering (SERS) and tip-enhanced Raman scattering (TERS). SERS is based on the enhancement of the phonon response from nanoobjects such as molecules or inorganic nanostructures placed on metal nanostruc-tured substrates with a localized surface plasmon resonance (LSPR). A drastic SERS enhancement for optical phonons in semiconductor nanostructures can be achieved by a proper choice of the plas-monic substrate, for which the LSPR energy coincides with the laser excitation energy. The resonant enhancement of the optical response makes it possible to detect mono-and submonolayer coatings of CdSe NCs. The combination of Raman scattering with atomic force microscopy (AFM) using a metallized probe represents the basis of TERS from semiconductor nanostructures and makes it possible to investigate their phonon properties with nanoscale spatial resolution. Gap-mode TERS provides further enhancement of Raman scattering by optical phonon modes of CdSe NCs with nanometer spatial resolution due to the highly localized electric field in the gap between the metal AFM tip and a plasmonic substrate and opens new pathways for the optical characterization of single semiconductor nanostructures and for revealing details of their phonon spectrum at the na-nometer scale.

AB - This work presents an overview of the latest results and new data on the optical response from spherical CdSe nanocrystals (NCs) obtained using surface-enhanced Raman scattering (SERS) and tip-enhanced Raman scattering (TERS). SERS is based on the enhancement of the phonon response from nanoobjects such as molecules or inorganic nanostructures placed on metal nanostruc-tured substrates with a localized surface plasmon resonance (LSPR). A drastic SERS enhancement for optical phonons in semiconductor nanostructures can be achieved by a proper choice of the plas-monic substrate, for which the LSPR energy coincides with the laser excitation energy. The resonant enhancement of the optical response makes it possible to detect mono-and submonolayer coatings of CdSe NCs. The combination of Raman scattering with atomic force microscopy (AFM) using a metallized probe represents the basis of TERS from semiconductor nanostructures and makes it possible to investigate their phonon properties with nanoscale spatial resolution. Gap-mode TERS provides further enhancement of Raman scattering by optical phonon modes of CdSe NCs with nanometer spatial resolution due to the highly localized electric field in the gap between the metal AFM tip and a plasmonic substrate and opens new pathways for the optical characterization of single semiconductor nanostructures and for revealing details of their phonon spectrum at the na-nometer scale.

KW - CdSe nanocrystals

KW - resonant TERS

KW - SERS

KW - surface enhanced Raman scattering

KW - TERS

KW - tip enhanced Raman scat-tering

UR - http://www.scopus.com/inward/record.url?scp=85132811901&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/4e7fb4ee-d289-31c1-81a7-700a3ee60fa5/

U2 - 10.3390/nano12132197

DO - 10.3390/nano12132197

M3 - Review article

C2 - 35808032

AN - SCOPUS:85132811901

VL - 12

JO - Nanomaterials

JF - Nanomaterials

SN - 2079-4991

IS - 13

M1 - 2197

ER -