Superfine Sr2CeO4 powder with blue-emission prepared by microemulsion method

Powder samples of Sr2CeO4 were prepared by microemulsion-heating method. Field emission scanning electron microscopy (FE-SEM) images showed that the sample fired at 850 °C for 4 h was spherical with an average diameter of 70∼80 nm while the samples which sintered at 900 °C for 4 h and 1000 °C for 4 h were shuttle-like shape and spherical respectively both with sizes less than 1 μm. X-ray diffraction (XRD) patterns disclosed that the superfine Sr2CeO4 exhibited an orthorhombic crystal structure. Room-temperature photoluminescence (PL) analysis indicated that there were three excitation peaks located at around 260, 280, and 350 nm, and all the Sr2CeO4 samples showed intensely blue emission at 470 nm. Compared with Sr2CeO4 samples prepared with other methods, the Sr2CeO4 phosphor fabricated with this method had a controllable shape with smaller size, lower calcination temperature, and shorter calcinations time.