VUV and UV–vis optical study on KGd2F7 luminescent host doped with terbium and co-doped with europium

The KGd2F7:Tb and KGd2F7:Tb,Eu samples were obtained using a solid state reaction. Excitation spectra and emission spectra are reported and analyzed within the VUV–UV–vis spectral range. The intense green luminescence is observed in the KGd2F7:Tb while the combined emission of terbium and europium in the KGd2F7:Tb,Eu covers substantially the region of white light. The materials under study can be effectively excited making use of intense f–d transitions of Tb3+ in the VUV–UV region. Experimental lifetimes of luminescent levels have been measured and discussed. It was found that the considerable energy transfer from Tb3+ to Eu3+ occurs.