The ultraviolet irradiation degradation of fluorescent lamp used BaMgAl10O17:Eu2+,Mn2+ phosphor

The ultraviolet irradiation degradation of lamps using BaMgAl10O17:Eu2+,Mn2+ phosphor is investigated. The X-ray photoelectron spectra demonstrate that the oxidation of Eu2+ is taking place during ultraviolet irradiation in air. The experiment in nitrogen indicates that the oxidation of Eu2+ is directly related to the oxygen in air and should be mainly responsible for the degradation of Eu2+. It reveals that the Mn2+ centers always remain stable during irradiation but its emission is involved in the energy transfer of Eu2+→Mn2+. Thus, the oxidation of Eu2+ also leads to the degradation of Mn2+.