Structural, luminescence and magnetic properties of Yb 3+ -Er 3+ codoped Gd 2 O 3 hierarchical architectures

In this paper, Gd(OH)3 microcrystals (MCs), with hierarchical dumbbell-like structures, were prepared via a one-step hydrothermal route using KOH as the alkaline source and ethylenediaminetetraacetic acid as the chelating reagent. XRD patterns and SEM images showed the typical hexagonal phase and the three-dimensional micro-dumbbell structure with an average length of 9 μm and diameter of 7 μm. The time dependent morphogenesis, the growth kinetic mechanism and the intrinsic electric field were exploited to demonstrate the formation mechanism of the Gd(OH)3 micro-dumbbell hierarchical architectures. Gd2O3 hierarchical MCs and their lanthanide-doped counterparts could also be obtained via heat treatment. Gd2O3:Yb3+/Er3+ hierarchical MCs exhibited relatively pure visible emission under near-infrared (980 nm) and violet (379.4 nm) excitation. Besides, NIR emission from Yb3+ 2F5/2 and Er3+ 4I13/2 was also found, which may be of particular interest for telecommunications applications. The possible energy transfer mechanisms were discussed. Moreover, Gd2O3 samples also have considerable magnetic mass susceptibility with a value of 1.321 × 10−4 emu g−1 Oe−1 by magnetic property studies. This work provides another path for preparing Gd2O3 hierarchical MCs.