Yellow–orange upconversion emission in Eu3+–Yb3+ codoped BaTiO3 phosphor

•The Eu3+–Yb3+ codoped BaTiO3 phosphor is prepared via co-precipitation method.•Upconversion emission is studied by 980 nm diode laser excitation.•The colour tunability has been observed.•The observed upconversion transitions have been explained thoroughly.•The material can be used in making the colour tunable display devices.

The Eu3+–Yb3+ codoped BaTiO3 phosphor is prepared via co-precipitation method and its upconversion emission is studied by 980 nm diode laser excitation. The X-ray diffraction pattern of the prepared sample showed the tetragonal BaTiO3 phase. The co-doped phosphor showed sharp upconversion emission bands peaking at ∼592, ∼614, ∼ 654, ∼704 and ∼796 nm due to the 5D0 → 7F1, 5D0 → 7F2, 5D0 → 7F3, 5D0 → 7F4 and 5D0 → 7F6 transitions, respectively of Eu3+ ions. The sharp band at 489 nm is assigned to the 2F5/2 → 2F7/2 transition of Yb3+ ion while the broad band around 505 nm is assigned to the defect states present in the sample. Based on the available experimental data, the process involved in the UC emissions has been explored and elaborated.

Graphical abstractUpconversion emission spectra of BaTiO3: Eu3+–Yb3+ phosphor at different concentrations.Figure optionsDownload full-size imageDownload as PowerPoint slide