CdSiO₃:Eu³⁺ nanophosphor: one pot synthesis and enhancement of orange–red emission through Li⁺ co-doping

In spite of high luminescence output of silicate based luminescence hosts, CdSiO₃ as potential luminescence host is not widely explored. In the current work we present a facile one step synthesis of CdSiO₃:Eu³⁺ host by using oxalyldihydrazide as fuel by solution combustion synthesis. The enhancement of the orange–red emission is achieved by charge compensation in the host by co-doping of monovalent lithium (Li⁺). X-ray diffraction studies show that CdSiO₃:Eu³⁺, Li⁺ stabilizes in monoclinic phase and with increase in Li⁺ addition crystallinity increases. Scanning electron microscopy, transmission electron microscopy (TEM) and high resolution TEM are carried out to determine the microstructure of the phosphor. The particles are found to be agglomerated and in the nano-regime. Photoluminescence studies show that the phosphor is excitable in the ultra-violet (UV), near-UV and UV blue regions, making it promising for technological applications. PL emission spectra shows that with increase of Li⁺ concentration orange-red emission at 612 nm increases and the optimum Li⁺ concentration was found to be x = 0.05. The emission intensity is enhanced by ~ threefold with Li⁺ doping. The enhancement in PL emission is explained by charge compensation mechanism and phosphor crystallinity. The colour purity of the phosphor calculated by CIE co-ordinates and Fred Schubert method were found to be (x = 0.298, y = 0.360) and 90% respectively.