Effect of cation mixing on luminescence of Eu in SrCl2

SrCl₂ forms solid solutions of various compositions with BaCl₂ and CaCl₂. Orthorhombic and tetragonal phases are also known to occur in the SrCl₂-CaCl₂ system. Though efficient emission of Eu²⁺ in SrCl₂ and CaCl₂ is known, there are no reports available on Eu²⁺ luminescence in the solid solutions and other phases. Investigations on these lines were carried out and the results are presented in this paper. Very intense emission comparable to that of the commercial lamp phosphors was observed for the solid solutions while the intensities for the orthorhombic and tetragonal phases are an order of magnitude smaller. Emission wavelengths do not vary much while excitation spectra for the solid solutions are much enhanced in the near UV region (350-400 nm). It is suggested that these results will be significant for developing phosphors with near UV excitations needed in applications such as solid state lighting.