Sol–gel synthesis and photoluminescence of K2NiF4-type structure phosphors CaxSr1−xGdyY1−yAlO4:zEu3+ with hybrid precursors

CaxSr1−xGdyY1−yAlO4:zEu3+ (x = 0.2–1.0, y = 0–1.0, z = 0.01–0.07) was synthesized by a hybrid precursor assembly sol–gel technology. We got sol solutions by stoichiometric rare earth nitrate, Sr(NO3)2, Ca(NO3)2, Al(NO3)3, at the same time investigated the relationship between the sol formed and experiment variable including Ph, temperature, concentration, and so on. Through drying and calcining precursors, we got luminescent materials powder. The particle size of luminescent materials is about 40 nm characterized by XRD and having thick three-dimension grains as SEM shown. Not only co-doping Ca2+ and Sr2+ but also changing the ratio of Gd3+ and Y3+ cannot change the crystalline structure in CaxSr1−xGdyY1−yAlO4, it also formed the crystalline structure as that of pure-phase CaGdAlO4. All these photoluminescence materials show good emission spectra and their luminescent intensity depend on the concentrating of Eu3+: in all these luminescent materials, there exist emission come from Eu3+ activator’ transitions of 5D0–7FJ (J = 0–3) and their emission intensity increase as adding to the concentration of Eu3+.