UV C luminescence of a modified zirconium silicate framework upon cathode ray and VUV excitation

Modification of K2ZrSi2O7 by the substitution of Zr by Hf shows that the incorporation of 20% Hf improves the PL of the material, while a complete replacement of Zr4+ by Hf4+ entirely quenches the charge-transfer based luminescence process. Quenching of the luminescence is also observed for the incorporation of Ln3+ (Ln = Ce, Pr, Tb). The emission band of K2(Zr,Hf)Si2O7 is nicely located in the UV-C range yielding an overlap with the germicidal activation curve (GAC) close to that of Lu2Si2O7:Pr, i.e. of about 55%. This finding brands the material as an interesting compound for radiation sources to be used in disinfection devices.