Open AccessIn situ XAFS experiments using a microfluidic cell: application to initial growth of CdSe nanocrystals
Author(s) -
Oyanagi H.,
Sun Z. H.,
Jiang Y.,
Uehara M.,
Nakamura H.,
Yamashita K.,
Zhang L.,
Lee C.,
Fukano A.,
Maeda H.
Publication year - 2011
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s0909049510050545
Subject(s) - x ray absorption fine structure , nucleation , extended x ray absorption fine structure , synchrotron , nanoparticle , xanes , materials science , nanocrystal , analytical chemistry (journal) , synchrotron radiation , particle (ecology) , absorption spectroscopy , chemical physics , spectral line , chemistry , nanotechnology , spectroscopy , optics , physics , oceanography , geology , organic chemistry , chromatography , quantum mechanics , astronomy
The design and performance of a compact fluorescense XAFS apparatus equipped with a microfluidic cell for in situ studies of nanoparticles are described. CdSe nanoparticles were prepared by solution reaction starting from trioctylphosphine‐Se. Time‐resolved experiments were performed by precisely controlling the reactor coordinates ( x , y ), allowing the synchrotron X‐ray beam to travel along a reactor channel, covering nucleation and initial growth of nanoparticles. Detailed analysis of EXAFS data combined with UV–vis spectra allow reliable estimation of particle size and density in the initial growth that cannot be accessible by conventional optical techniques based on a long‐range order. The Se K ‐XANES spectra are interpreted by multi‐scattering calculations providing bond formation kinetics consistent with the EXAFS data.