Luminescence efficiencies of self- and Tm3+ activated CaWO4 under vacuum ultraviolet radiation excitation

► Luminescence efficiency of CaWO4 under 147 VUV excitation is 90% of that of BaMgAl10O17:Eu2+ commercial PDP phosphor. ► However, its color purity (400 nm emission) and particle size needs modification for PDP application. ► CaWO4:Tm exhibits better color rendering but its efficiency to 147 nm VUV is only 60% of that of CaWO4. ► Therefore other methods to shift the WO4 emission to bluish region such as mixed tungstates are proposed. ► Green emission related to oxygen vacancies in CaWO4 could be reduced with suitable doping or annealing procedures.