We present a combined real and reciprocal space structural and microstructural characterization of CeO2 nanoparticles (NPs) exhibiting different crystallite sizes; similar to 3 nm CeO2 NPs were produced by an inverse micellae wet synthetic path and then annealed at different temperatures. X-ray total scattering data were analyzed by combining real-space-based Pair Distribution Function analysis and the reciprocal-space-based Debye Scattering Equation method with atomistic models. Subtle atomic-scale relaxations occur at the nanocrystal surface. The structural analysis was corroborated by ab initio DFT and force field calculations; micro-Raman and electron spin resonance added important insights to the NPs' defective structure. The combination of the above techniques suggests a core-shell like structure of ultrasmall NPs. These exhibit an expanded outer shell having a defective fluorite structure, while the inner shell is similar to the bulk structure. The presence of partially reduced O-2(-delta) species testifies to the high surface activity of the NPs. On increasing the annealing temperature, the particle dimensions increase, limiting disorder as a consequence of the progressive surface-to-volume ratio reduction.

Structure and Surface Relaxation of CeO2 Nanoparticles Unveiled by Combining Real and Reciprocal Space Total Scattering Analysis / M. Scavini, F. Bertolotti, J. Mlloja, F. Umbri, A. Bosc, S. Cappelli, S. Checchia, C. Oliva, P. Fumagalli, D. Ceresoli, M. Longhi, A. Guagliardi, M. Coduri. - In: NANOMATERIALS. - ISSN 2079-4991. - 12:19(2022 Sep 27), pp. 3385.1-3385.25. [10.3390/nano12193385]

Structure and Surface Relaxation of CeO2 Nanoparticles Unveiled by Combining Real and Reciprocal Space Total Scattering Analysis

M. Scavini
Primo
Conceptualization
;
F. Umbri;S. Cappelli;C. Oliva;P. Fumagalli;M. Longhi;
2022

Abstract

We present a combined real and reciprocal space structural and microstructural characterization of CeO2 nanoparticles (NPs) exhibiting different crystallite sizes; similar to 3 nm CeO2 NPs were produced by an inverse micellae wet synthetic path and then annealed at different temperatures. X-ray total scattering data were analyzed by combining real-space-based Pair Distribution Function analysis and the reciprocal-space-based Debye Scattering Equation method with atomistic models. Subtle atomic-scale relaxations occur at the nanocrystal surface. The structural analysis was corroborated by ab initio DFT and force field calculations; micro-Raman and electron spin resonance added important insights to the NPs' defective structure. The combination of the above techniques suggests a core-shell like structure of ultrasmall NPs. These exhibit an expanded outer shell having a defective fluorite structure, while the inner shell is similar to the bulk structure. The presence of partially reduced O-2(-delta) species testifies to the high surface activity of the NPs. On increasing the annealing temperature, the particle dimensions increase, limiting disorder as a consequence of the progressive surface-to-volume ratio reduction.
Debye Scattering Equation; ESR; Pair Distribution Function; Raman spectroscopy; atomistic simulations; ceria nanoparticles; total scattering
Settore CHIM/02 - Chimica Fisica
Settore CHIM/03 - Chimica Generale e Inorganica
Settore FIS/01 - Fisica Sperimentale
PSRL218LPRAT_01 - Piano di Sostegno alla Ricerca 2015-2017 - Linea 2 "Dotazione annuale per attività istituzionali" (anno 2018) - PRATI, LAURA - PSR_LINEA2_ / Piano di sviluppo di ricerca - Dotazioni dipartimentali - Linea 2 - 2018
Article (author)
File in questo prodotto:
File Dimensione Formato  
84_Nanomater.12(2022)3385_1-25.pdf

accesso aperto

Tipologia: Publisher's version/PDF
Dimensione 1.67 MB
Formato Adobe PDF
1.67 MB Adobe PDF Visualizza/Apri
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/945282
Citazioni
  • ???jsp.display-item.citation.pmc??? 0
  • Scopus 0
  • ???jsp.display-item.citation.isi??? 0
social impact