Luminescence properties of Tb3+ and Eu3+ doped beyerite CaBi2O2(CO3)2

Mineral Beyerite belonging to the sillen family consisting of [Bi2O2](2+) layers along with Ca2+ ions possesses a layer sequence of (Bi2O2)(2+)-CO32--Ca2+-CO32--(Bi2O2)(2+) in such a way that the plane of the (CO3)(2-) group is orthogonal to the plane of the layer. By employing a single step hydrothermal process, beyerite, Tb3+, Eu3+ incorporated beyerite along with codoped Tb3+/Eu3+ samples of beyerite have been successfully synthesized. The samples were characterized by powder X-ray diffraction combined with Rietveld refinement, fourier transform infrared spectra, diffuse reflectance and photoluminescent measurements. Emission characteristics of Tb3+ and Eu3+ samples under excitation in the UV region showed excellent luminescent properties in the visible region confirming the presence of rare earth dopants. Tunable colors in a wide range is also possible by varying the relative doping ratios of Tb3+ and Eu3+ in the codoped beyerite samples indicating CaBi2O2(CO3)(2) to be a potential host lattice. (C) 2017 Elsevier Ltd. All rights reserved.