| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 741916 | Sensors and Actuators B: Chemical | 2015 | 8 Pages |
•Synthesis of Ho3+–Yb3+–Mg2+ codoped CaMoO4 phosphor by coprecipitation route.•Study of upconversion properties of prepared materials.•Mg2+ ion incorporation causes luminescence improvement.•Investigation of optical temperature sensing behaviour.
The CaMoO4 phosphors codoped with Ho3+, Yb3+, Mg2+ ions, synthesized by chemical coprecipitation route and characterized structurally by X-ray diffraction analysis have shown the tetragonal phase of CaMoO4. The codoping with Mg2+ ion causes shrinkage in the lattice dimension due to substitutional effect. For the investigation of particle size and the surface morphology of the prepared material the high resolution transmission electron microscopy (HRTEM) and field emission scanning electron microscopy (FESEM) analysis have been performed respectively. The prepared phosphor powders upon excitation with 980 nm laser radiation give intense red (660 nm) and green (545 nm) UC emissions along with weak blue (460 nm, 489 nm) and near infrared (756 nm) emission bands. The enhancement in the upconversion (UC) emission intensity has been observed due to codoping with Mg2+ ions. The lifetime corresponding to 5F4, 5S2 → 5I8, 5F5 → 5I8 transitions have been analyzed to cross-check the UC mechanism. The effect of variation of pump power and also the external temperature on the blue emission bands corresponding to the 3K8 → 5I8 and 5F3 → 5I8 transitions respectively have been monitored to investigate the sensing property of the phosphor.
Graphical abstractEnhancement in UC emission and reduction in lifetime of the emitting level due to codoping.Figure optionsDownload full-size imageDownload as PowerPoint slide
