Please use this identifier to cite or link to this item: http://hdl.handle.net/1822/39730

TitleEffect of acid or alkaline catalyst and of different capping agents on the optical properties of CdS nanoparticles incorporated within a diureasil hybrid matrix
Author(s)Gonçalves, L. F. F. F.
Silva, Carlos J. R.
Kanodarwala, F. K.
Stride, J. A.
Pereira, Mário R.
KeywordsNanocomposites
CdS nanoparticles Luminescence
Luminescence
Diureasil
CdS nanoparticles
Issue date2015
PublisherElsevier
JournalOptical Materials
CitationGonçalves, L. F. F. F., Silva, C. J. R., Kanodarwala, F. K., Stride, J. A., & Pereira, M. R. (2015). Effect of acid or alkaline catalyst and of different capping agents on the optical properties of CdS nanoparticles incorporated within a diureasil hybrid matrix. Optical Materials, 49, 171-181. doi: 10.1016/j.optmat.2015.09.007
Abstract(s)CdS nanoparticles (NPs) were synthesized using colloidal methods and incorporated within a diureasil hybrid matrix. The surface capping of the CdS NPs by 3-mercaptopropyltrimethoxysilane (MPTMS) and 3-aminopropyltrimethoxysilane (APTMS) organic ligands during the incorporation of the NPs within the hybrid matrix has been investigated. The matrix is based on poly(ethylene oxide)/poly(propylene oxide) chains grafted to a siliceous skeleton through urea bonds and was produced by sol–gel process. Both alkaline and acidic catalysis of the sol–gel reaction were used to evaluate the effect of each organic ligand on the optical properties of the CdS NPs. The hybrid materials were characterized by absorption, steady-state and time-resolved photoluminescence spectroscopy and High Resolution Transmission Electron Microscopy (HR-TEM). The preservation of the optical properties of the CdS NPs within the diureasil hybrids was dependent on the experimental conditions used. Both organic ligands (APTMS and MPTMS) demonstrated to be crucial in avoiding the increase of size distribution and clustering of the NPs within the hybrid matrix. The use of organic ligands was also shown to influence the level of interaction between the hybrid host and the CdS NPs. The CdS NPs showed large Stokes shifts and long average lifetimes, both in colloidal solution and in the xerogels, due to the origin of the PL emission in surface states. The CdS NPs capped with MPTMS have lower PL lifetimes compared to the other xerogel samples but still larger than the CdS NPs in the original colloidal solution. An increase in PL lifetimes of the NPs after their incorporation within the hybrid matrix is related to interaction between the NPs and the hybrid host matrix.
TypeArticle
URIhttp://hdl.handle.net/1822/39730
DOI10.1016/j.optmat.2015.09.007
ISSN0925-3467
Peer-Reviewedyes
AccessRestricted access (UMinho)
Appears in Collections:CDQuim - Artigos (Papers)

Files in This Item:
File Description SizeFormat 
OptMat_49(2015)171-181.pdf
  Restricted access
2,11 MBAdobe PDFView/Open

Partilhe no FacebookPartilhe no TwitterPartilhe no DeliciousPartilhe no LinkedInPartilhe no DiggAdicionar ao Google BookmarksPartilhe no MySpacePartilhe no Orkut
Exporte no formato BibTex mendeley Exporte no formato Endnote Adicione ao seu ORCID