A benign approach for tailoring the photometric properties and Judd-Ofelt analysis of LaAlO3:Sm3+ nanophosphors for thermal sensor and WLED applications

• Published in: Sensors and actuators. B, Chemical Vol. 243; pp. 1057 - 1066
• Main Authors: Manohar, T., Prashantha, S.C., Naik, Ramachandra, Nagabhushana, H., Nagaswarupa, H.P., Anantharaju, K.S., Girish, K.M., Premkumar, H.B.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.05.2017
• Subjects: CIE n CCT; Diffuse reflectance; LaAlO3:Sm3; Photoluminescence; Thermal sensor; LaAlO3:Sm3; Diffuse reflectance; Thermal sensor; CIE n CCT; Photoluminescence
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2016.12.080

[Display omitted] •Nanophosphors of LaAlO3:Sm3+ − prepared by facile LCS method.•DRS records absorption bands due to f–f transition of Sm3+ ions.•Characteristic emission peak of Sm3+ ion was recorded at 611nm.•CIE co-ordinate values lies in white region.•LaAlO3: Sm3+ was quite useful for WLEDs, display and thermal sensor applications. Sm3+ doped (1–9mol%) Lanthanum aluminate (LaAlO3) nanophosphor was prepared by solution combustion synthesis and characterized by photoluminescence (PL), powder X-ray diffraction (PXRD), UV–vis (UV-vis), scanning and transmission electron microscopy (SEM and TEM). PL excitation and emission spectra, quantum efficiency, luminescence life time were studied to investigate the luminescence properties of LaAlO3:Sm3+ nanophosphor, effectively excited by near UV wavelength 406nm. The combination of different coloured emissions in visible region presents a desired white light which leads to the WLED application. The chromaticity coordinates of the optimized concentration of Sm3+ was estimated to be (0.3684, 0.4066) and the corresponding correlated color temperature (CCT) was found to be ∼4485K which favors in warm white light emissive display applications. The luminescence quantum efficiency was calculated from the emission spectra using Judd–Ofelt (J-O) theory. From the analysis the estimated branching ratio (∼56%) was greater than 50%, as a result the phosphor was highly suitable for display devices. The present phosphor was highly useful as thermal sensor in the temperature interval between 100 to 400°C as estimated from decay time measurements.