Temperature dependence of photoluminescence property in BaIn₂O₄

The temperature-dependent photoluminescence (PL) spectra of BaIn₂O₄, prepared by coprecipitation, are measured and discussed. Aside from the reported 3.02-eV violet emission, the 1.81-eV yellow emission involved with oxygen vacancy is also observed at room temperature wherein the deep donor level is at 1.2 eV. With the temperature increasing, the peak energies for both emissions show a red shift. Moreover, the yellow emission intensity decreases while the violet emission intensity increases. The temperature dependence of the yellow emission intensity fits very well into the one-step quenching process equation, indicating a fitted activation energy at 19.2 meV.