Electronic properties and europium ion photoluminescence behaviors in Sr2CeO4 phosphor

Sr2CeO4, pure and doped with Eu3+ ions of different concentrations, were synthesized by polyacrylamide gel method. First principles were applied to calculate the electronic structures and band gap of Sr2CeO4. The results show that a broad emission band originating from Sr2CeO4 host and Eu3+ emission lines in blue, green, and red regions coexist. The increase in Eu3+ concentration results in the luminescence intensity redistribution between the Sr2CeO4 host and the doping ion. The energy transfer model clarifies the possible mechanisms of energy transfer from Sr2CeO4 host to Eu3+ in Sr2CeO4:Eu3+ phosphor.

Research highlights▶ The theoretical result of Eg, which is 2.64  eV, agrees well with the experiment. ▶ The valence and conduction bands are mainly of O 2p and Ce 4f orbital, respectively. ▶ The energy transfer is from Sr2CeO4 host to Eu3+ in Sr2CeO4:Eu3+ phosphor.