Enhanced luminescence in CaMoO4: Eu3+ red phosphor nanoparticles prepared by mechanochemically assisted solid state meta-thesis reaction method

For the first time, CaMoO4: xEu(3+) (x = 0.02, 0.04, 0.06, 0.08, 0.1) red phosphor nanoparticles were synthesized using the simple mechanochemically assisted solid state meta-thesis (SSM) reaction method and the luminescence properties as a function of Eu3+ ion concentration was investigated. The characteristics of the phosphor materials were analyzed using X-ray diffraction, fourier transform infrared spectroscopy, photoluminescence (PL) and diffuse reflectance spectroscopy. For 8 mol% of Eu3+ concentration, the phosphor shows an intensified excitation peak at 392 nm indicating a strong absorption. The PL emission spectra of CaMoO4: Eu3+ phosphors showed an intense peak at 615 nm (red) which corresponds to D-5(0) - \u3e F-7(2) transition of Eu3+. The optimal Eu3+ concentration in CaMoO4 phosphors for enhanced red emission occurs for 8 mol% and above this concentration, the emission intensity decreases due to quenching effect. The CIE colour coordinates of the CaMoO4: 0.08Eu(3+) red phosphor coincide very well with the standard values of NTSC. The red emission intensity of the SSM prepared CaMoO4: 0.08Eu(3+) red phosphor is 4.7 times greater than that of the commercial Y2O2S: Eu3+ red phosphor and 1.6 times more than the same phosphor prepared by the solid state reaction method