Skip to main content

Advertisement

Log in

Gold nanoparticles enclosed in silica xerogels by high-pressure processing

  • Research Paper
  • Published:
Journal of Nanoparticle Research Aims and scope Submit manuscript

Abstract

The dispersion of gold nanoparticles (AuNPs) in solid matrices, maintaining their optical properties as in liquid medium, has been explored, enlarging the possibilities of handling and applications of these nanoparticles. In this study, AuNPs were successfully enclosed in silica using the sol–gel method and high-pressure processing at 7.7 GPa, at room temperature, obtaining compacts with densities as high as 85% of silica glass and Vickers microhardness of 50% of quartz. This densification was confirmed by the reduced values of specific surface area and closed pores. UV–Vis spectra showed that the AuNPs maintain their optical properties, in the monoliths and in the compacts, presenting an absorption band in the characteristic region of AuNPs smaller than 20 nm. The slight red-shifts of the absorption peaks cannot be explained in the same way as for AuNPs in solution, where it is associated to an increase in particle diameter. In solid samples, additional factors as matrix properties should be considered. Transmission electron microscopy (TEM) images showed that the AuNPs have spherical shape both in solution and in the monolith, with an average diameter not exceeding 10 nm. It was also observed that the high-pressure processing did not destroy or misshape the AuNPs.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12

Similar content being viewed by others

References

Download references

Acknowledgments

The authors would like to thank CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico) and CEME-UFRGS (Centro de Microscopia Eletrônica da Universidade Federal do Rio Grande do Sul), Brazil. MRG and TMHC also thank AFOSR (Air Force Office for Scientific Research) for grant FA9550-08-1-0426, USA.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to T. M. H. Costa.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Laranjo, M.T., Kist, T.B.L., Benvenutti, E.V. et al. Gold nanoparticles enclosed in silica xerogels by high-pressure processing. J Nanopart Res 13, 4987–4995 (2011). https://doi.org/10.1007/s11051-011-0480-2

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11051-011-0480-2

Keywords

Navigation