Low-energy-loss EFTEM imaging of thick particles and aggregates.
Electron spectroscopy imaging is a powerful tool for the elucidation of colloidal particle morphology and microchemistry, but it normally requires the use of very thin samples, typically less than 50 nm, to avoid the effects of multiple scattering. This work shows that many aspects of the internal morphology of thick particles and aggregates and the chemical component distribution are revealed using low-energy-loss electron imaging in the transmission electron microscope, benefiting from multiple scattering as well as small but significant differences in the low-energy-loss spectra of aggregate constituents. Low-loss images reveal morphological details of thick aggregates made out of colloidal polymers (natural rubber and styrene-acrylic latex) and inorganic particles (silica, montmorillonite, and aluminum phosphate) at a spatial resolution close to that achieved in the bright-field images and much better than in the elemental maps, showing the advantages of the simultaneous use of low-loss images and standard thin-cut elemental maps.
Valadares
Leonardo Fonseca
LF
Institute of Chemistry, Universidade Estadual de Campinas, Caixa Postal 6154, 13084-971 Campinas, SP, Brazil.
do Carmo Bragança
Fábio
F
da Silva
Cristiane Aparecida
CA
Leite
Carlos Alberto Paula
CA
Galembeck
Fernando
F