SER(R)S of porphyrins on Ag nanoparticles immobilized by silane: unique way how to obtain free base porphyrin spectra
2007
Abstract
We measured surface-enhanced resonance Raman scattering (SERRS) spectra of 5,10,15,20-tetrakis(1-methyl-4-pyridyl) porphyrin (TMPyP) by using of solid SERS-active substrates: Ag nanoparticles immobilized by aminosilane to glass plates. We report surprising result that by using such substrates it is possible to obtain SERRS spectra of porphyrins in unperturbed free base form, although by using the silver nanoparticles directly in solution, porphyrin molecules are completely metalated.
We suggest that silane used for nanoparticle immobilization modifies surface properties and thus, make porphyrin metalation impossible.