An X-ray Absorption Spectroscopy Study of the Ni K Edge in NiO−SiO2 Nanocomposite Materials Prepared by the Sol−Gel Method

Autor:	Gavin Mountjoy, Anna Corrias, G. Piccaluga, S. Solinas
Rok vydání:	1999
Předmět:	X-ray absorption spectroscopy Nanocomposite Materials science Absorption spectroscopy Extended X-ray absorption fine structure Nickel oxide Non-blocking I/O Materials Chemistry Analytical chemistry Crystallite Physical and Theoretical Chemistry XANES Surfaces Coatings and Films
Zdroj:	The Journal of Physical Chemistry B. 103:10081-10086
ISSN:	1520-5207 1520-6106
Popis:	EXAFS (extended X-ray absorption fine structure) and XANES (X-ray absorption near edge structure) techniques have been used to study the structural evolution of nanocomposites constituted of nickel oxide nanoparticles embedded into an amorphous silica matrix during their sol-gel preparation. EXAFS data show that no interaction between the metal oxide nanoparticles and the silica network develops since the spectra of all the samples have a structure very similar to that of crystalline NiO. Quantitative information obtained from the fitting of the data using a full multiple scattering calculation shows that the reduction of the EXAFS oscillations in the nanocomposite samples is mainly related to an increase of disorder of the superficial sites while there was no evidence of a significant reduction of coordination numbers due to the size of the crystallites. XANES results support the conclusion that the structure of the nanocomposites is very similar to that of crystalline NiO.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::4be18b71ec5e6e7061a8230e5b06ef83 https://doi.org/10.1021/jp9927911 Zobrazit plný text záznamu