Core-Shell Structure in Doped Inorganic Nanoparticles: Approaches for Optimizing Luminescence Properties

Figure 2

Transmission electron microscopy (TEM) photographs of silica-coated Y₂O₃:Tm³⁺,Yb³⁺ NPs for the sintering time of 60 min and the coating time of 30 min (a), 60 min (b), 90 min (c), and 120 min (d), respectively. The upper inset (c) shows the electron diffraction (ED) pattern of noncrystalline silica shells and the lower inset is the corresponding ED pattern of crystalline Y₂O₃:Tm³⁺,Yb³⁺ core [44]. Copyright 2008 American Institute of Physics.

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