Effects of solvent and additive on controllable mineralization of MCO3 (M = Ca, Ba, Sr) crystals and their applications as red phosphors doped with Eu3+ ions

Abstract

In this work, a series of carbonate minerals including CaCO 3 , BaCO 3 and SrCO 3 have been prepared in H 2 O-ethylene glycol (EG) solution at room temperature, which further serve as hosts to prepare the phosphors doped with Eu 3+ . The as-obtained samples were characterized by means of XRPD, FESEM, and PL techniques. The experimental results reveal that the volume composition of mixed solvents and additives were crucial for producing samples with discriminating size, shape and phase. In addition, the luminescent properties of CaCO 3 : Eu 3+ , BaCO 3 : Eu 3+ , and SrCO 3 : Eu 3+ phosphors were briefly studied by excitation spectra, and emission spectra. Remarkably, many scientific merits involved in this study might appear as follows: (1) simply changing the solvent composition or adding additives in mixed solution can realize the crystal growth of carbonates with controlled size, shape and phase; and(2) the as-prepared phosphors doped with Eu 3+ could be directly crystallized from an aqueous solution at room temperature without subsequent calcinations.

Mineralization of wood by calcium carbonate insertion for improved flame retardancy

“…However, a closer look reveals that the resultant mineralization product is a mixture of calcite and vaterite according to X-ray powder diffraction ( Figure 3) and Raman spectroscopy (Figure 4) both in spruce or beech. Under the present reaction conditions (pH≈8.2), the initially formed metastable vaterite is expected to gradually transform into calcite (Spanos and Koutsoukos 1998;Sheng Han et al 2006;Bao et al 2011). Vaterite, however, is remarkably stable in dry wood samples over several months, which might be explained by the effect of confined spaces in the wood microstructure.…”

High-yield synthesis of vaterite CaCO3 microspheres in ethanol/water: structural characterization and formation mechanisms

“…However, vaterite is traditionally used as good filler for the improvement of material mechanical properties in industrial production. Though many works have been reported on the synthesis of vaterite with different methods [9][10][11][12][13], there remains a large challenge of synthesizing large-scale pure vaterite in aqueous solution, because the synthesized vaterite usually coexists with the other two polymorphs, calcite and aragonite. Currently, a variety of CaCO 3 crystals with different morphologies including hollow spheres, flowers, spherules, rhombohedra, and dumbbells have been prepared.…”

Luminescent properties and energy transfer of Gd3+/Eu3+ co-doped cubic CaCO3

“…Calcium carbonate, as a representative bio-mineral system, is abundant in nature and has thus far provided much impetus for understanding the process of bio-mineralization. As an important industrial substance, CaCO 3 was widely used in areas of rubber, paints, paper, and plastics [12]. As a host, calcium carbonate was utilized to synthesize luminescent materials for their excellent chemical and thermal stability, high rigidity, as well as good absorption for UV light and low cost [13][14].…”