Tuning the emission color and temperature range of dual-mode luminescent thermometer by dopant valence states control

Dual emitting materials are of great interest for luminescence thermometry. The operating temperature range, the thermal sensitivity as well emission color crucial parameters, which define competitiveness sensor. In this work, we propose a new and convenient method modulation range through control dopant oxidation states crystal field variations. To end, investigated inorganic phosphors in two valence Mn luminescent centers can be stabilized. When inserted octahedral environment, Mn4+ ions present red (2E → 4A2 transition), whereas Mn2+ exhibit green tetrahedral environment (4T1 6A1 transition). Due to different behavior properties according temperature, resulting varies from exploited visual detection. We demonstrate proportion finely tuned, owing thermally driven reduction, allows modulate change at specific temperature. Two isostructural were investigated, SrMgAl10O17:Mn4+,Mn2+ BaMgAl10O17:Mn4+,Mn2+, envisioned competitive ratiometric colorimetric thermometer, with tunable properties.