Saltar al contenido
MilliporeSigma

Quantum confinement effects on charge-transfer between PbS quantum dots and 4-mercaptopyridine.

The Journal of chemical physics (2011-01-19)
Xiaoqi Fu, Yi Pan, Xin Wang, John R Lombardi
RESUMEN

We obtain the surface enhanced Raman spectra of 4-mercaptopyridine on lead sulfide (PbS) quantum dots as a function of nanoparticle size and excitation wavelength. The nanoparticle radii are selected to be less than the exciton Bohr radius of PbS, enabling the observation of quantum confinement effects on the spectrum. We utilize the variation of nontotally symmetric modes of both b(1) and b(2) symmetry as compared to the totally symmetric a(1) modes to measure the degree of charge-transfer between the molecule and quantum dot. We find both size dependent and wavelength dependent resonances in the range of these measurements, and attribute them to charge-transfer resonances which are responsible for the Raman enhancement.

MATERIALES
Referencia del producto
Marca
Descripción del producto

Sigma-Aldrich
4-Mercaptopyridine, 95%