Hydrothermal synthesis and luminescence of NaGd(WO4)2:RE3+ (RE = Eu, Tb, Tm) phosphors

NaGd(WO4)(2):RE3+ (RE = Eu, Tb, Tm) phosphors were synthesized by a hydrothermal process. The XRD and FTIR results show that the hydrothermal time has obvious influence on the crystallization of samples. The longer hydrothermal time benefits to the higher crystallization of NaGd(WO4)(2):RE3+ samples. All of the excitation spectra of NaGd(WO4)(2):RE3+ samples show the charge transfer bands, which suggests the effective energy transfer between the WO42- group and RE3+ ions. Under the excitation of 288 nm, NaGd(WO4)(2):RE3+ (RE = Eu, Tb, Tm) phosphors show emissions in red, green, and blue regions, respectively. The results of this work indicate that NaGd(WO4)(2):RE3+ (RE = Eu, Tb, Tm) phosphors have potentials to be used as red, green, and blue emitting phosphors.