# Effect of Ionic Liquids on the Structural Properties of SBA-15/CeO2 Nanocomposites

## TL;DR

This paper investigates how ionic liquids affect the structure of SBA-15/CeO2 nanocomposites, which could be useful in catalysis and adsorption.

## Contribution

The study reveals how specific ionic liquids influence the structural and surface properties of SBA-15/CeO2 nanocomposites.

## Key findings

- SAXS, XRD, and TEM confirmed the formation of ordered mesoporous structures and CeO2 nanoparticles.
- XPS analysis showed the presence of Ce3+ and Ce4+ ions, linked to oxygen vacancies in CeO2.
- SEM images revealed that ionic liquids significantly affect the morphology of the nanocomposites.

## Abstract

Ordered mesoporous silica materials have attracted considerable
attention due to their unique structural, textural, and morphological
properties, alongside their versatile applications in catalysis, adsorption,
and drug delivery systems. This study explores the influence of ionic
liquids (ILs) on the synthesis of SBA-15 and SBA-15/CeO2 nanocomposites. DMIBr (1-dodecyl-3-methylimidazolium bromide) and
DMIBF4(1-dodecyl-3-methylimidazolium tetrafluoroborate)
were the analyzed ILs. The objective was to evaluate how these ILs
modulate the structural, textural, and morphological properties of
the resulting nanocomposites. SAXS analysis confirmed the formation
of well-ordered mesoporous structures with hexagonal arrangements,
corroborating with physisorption data and TEM images. XRD measurements
confirmed the presence of CeO2 nanoparticles within the
nanocomposites, exhibiting a fluorite-type cubic crystal structure,
supported by Raman spectroscopy, which identified characteristic peaks
corresponding to Ce–O vibrational modes. XPS analysis provided
detailed insights into the surface chemistry, revealing the presence
of Ce3+ and Ce4+ ions, oxygen species, and their
interaction with the silica matrix. The Ce3+ ions, associated
with oxygen vacancies in the CeO2 lattice, were identified
as key active sites for adsorption and catalysis. SEM images displayed
distinct morphologies of the nanocomposites, attributed to the specific
used IL. These results underscore the pivotal role of ILs in tailoring
the properties of SBA-15/CeO2 nanocomposites, offering
valuable knowledge for their potential applications in diverse fields.