Journal of Sol-Gel Science and Technology

, Volume 89, Issue 3, pp 785–795 | Cite as

Mesoporous silica modified luminescent Gd2O3:Eu nanoparticles: physicochemical and luminescence properties

  • Ali AldalbahiEmail author
  • Mostafizur Rahaman
  • Anees A. AnsariEmail author
Original Paper: Sol-gel and hybrid materials for optical, photonic and optoelectronic applications


Highly colloidal Gd2O3:Eu nanoparticles (core-NPs) were synthesized by thermal decomposition via weak base at low temperature. The sol–gel chemical process was employed for silica layer surface coating to increase solubility, colloidal stability, biocompatibility, and non-toxicity at the ambient conditions. XRD results indicate the highly purified, crystalline, single phase, and cubic phase Gd2O3 nanocrystals. TEM image shows that the mesoporous thick silica layer was effectively coated on the core nanocrystals, which have irregular size with nearly spherical shape and grain size about 10–30 nm. An absorption spectra and zeta potential results in aqueous media revealed that solubility, colloidal stability, and biocompatibility character were enhanced from core to core–shell structure because of silica layer surface encapsulation. The samples, demonstrated excellent photoluminescence properties (dominant emission 5D0 → 7F2 transition in the red region at 610 nm), indicated to be used in optical bio-detection, bio-labeling, etc. The photoluminescence intensity of the silica shell modified core/shell NPs was suppressed relatively core-NPs; it indicates the multi-photon relaxation pathways arising from the surface coated high vibrational energy molecules of the silanol groups. The core/nSiO2/mSiO2 nanocrystals display strong emission (5D0 → 7F2) transition along with excellent solubility and biocompatibility, which may find promising applications in the photonic based biomedical field.


  • • Multi-silica layers coated luminescent Gd2O3:Eu@nSiO2@mSiO2 core–shell nanoparticles.

  • • Mesoporous, highly aqueous dispersible core-shell nanoparticles.

  • • Impact of silica shell on physiochemical properties.

  • • Excellent absorbance and photoluminescence properties.


Gadolinium oxide Mesoporous silica Biocompatible Zeta potential Luminescence properties 



The authors extend their appreciation to the Deanship of Scientific Research at King Saud University for funding this work through Research Group No. RG-1436-005.

Authors contributions

The idea is from Dr. Ali Aldalbahi and Dr. Anees A Ansari, the manuscript was mainly written by AAA and AA. MR helped in the technical support for the characterization. All authors read and approved the final manuscript. and there is no conflict of interest.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Authors and Affiliations

  1. 1.King Abdullah Institute for NanotechnologyKing Saud UniversityRiyadhSaudi Arabia
  2. 2.Department of Chemistry, College of ScienceKing Saud UniversityRiyadhSaudi Arabia

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