Evaluation of Li2SnO3:Cr3+, Mn4+ as a dual-emitter luminescence sensor for cryogenic temperatures

• Published in: Journal of materials chemistry. C, Materials for optical and electronic devices Materials for optical and electronic devices, 2024-01, Vol.12 (4), p.1341-1353
• Main Authors: Mykhaylyk, V, Zhydachevskyy, Y, Kraus, H, Stasiv, V, Leniec, G, Hreb, V, Vasylechko, L, Sydorchuk, V, Suchocki, A
• Format: Article
• Language: English
• Subjects: Cryogenic temperature; Electron paramagnetic resonance; Emission analysis; Emitters; Field strength; Luminescence; Manganese ions; Optical properties; Photoluminescence; Sensitivity; Sensors; Temperature; Temperature sensors; Time constant; Transition metals; Trivalent chromium; X ray powder diffraction
• ISSN: 2050-7526; 2050-7534
• DOI: 10.1039/d3tc03913g

The sensitivity of luminescence properties in materials doped with transition metal (TM) ions to changes of temperature makes them particularly promising for thermometric applications. Designing and optimizing such materials requires a deep understanding of their structure, local environment of emission centres, and luminescence processes. In this work, we investigate the potential of Li2SnO3 doped with Cr3+ and Mn4+ as a dual-emitting luminescence temperature sensor. Li2SnO3 was chosen as the host material due to it being able to host both Cr3+ and Mn4+ at Sn octahedral positions. As a result, Mn4+ ions exhibit a distinctive 2E → 4A2 line emission due to a strong crystal field, and Cr3+ ions experience an intermediate crystal field strength resulting in both, 2E → 4A2 and 4T2 → 4A2 emissions. Through thorough examination, using powder X-ray diffraction (XRD), electron paramagnetic resonance (EPR) and photoluminescence techniques we identified two distinct types of [SnO6] octahedral centers that correspond to two types of slightly different Cr3+ and Mn4+ emission centers in the Li2SnO3 structure. The high sensitivity of the decay time constant for the 2E → 4A2 emission of Li2SnO3–Cr3+, Mn4+ to temperature changes (2.0%/K at 190 K and 5.8%/K at 220 K for Cr3+ and Mn4+, respectively) positions the material as an attractive non-contact temperature sensor. Furthermore, application of such a dual-emitter luminescence material as a temperature sensor expands its sensitivity across a broader temperature range and offers the additional advantage of cross-checking measurements compared to materials solely doped with Cr3+ or Mn4+.