Synthesis and down conversion emission property of Eu3+ doped LaAlO3 CsAlO2 and LiLaO2 phosphors

[EN] LaAlO3:Eu3+, CsAlO2:Eu3+ and LiLaO2:Eu3+ phosphors with varying concen- trations of Eu3+ from 3 to 10 mol% were prepared by combustion synthesis method and the samples were further heated to 1,000ºC to improve the crystallinity of the materials. The structure and morphology of materials have been examined by X-ray diffraction and scan- ning electron microscopy. SEM images depicted that the morphology of crystallites have no uniform shapes and sizes. Small and coagulated particles of irregular shapes of different sizes are obtained. The characteristic emissions of Eu3+ were clearly observed at nearly 580, 592, 650, 682 to 709 (multiplet structure) nm for 5D - 7 Fn transitions where n = 0, 1, 3, 4 respectively, including the strongest emission peaks at 614 and 620 nm for 5 D0 - 7 F2 transitions in CsAlO2:Eu3+ and LiLaO2:Eu3+ host lattices. The intensity of emission peak corresponding to 5 D0 !→ 7 F1 transitions in LaAlO3 :Eu3+ material is comparable to that of 5D0 5D-7F2 transitions which is also a singlet. Photoluminescence intensity follows the order as in LiLaO2 > LaAlO3 > CsAlO2 lattices. Remarkable high photoluminescence intensity with 7 mol% doping of Eu3+ in LiLaO2 makes it a strong contender for red colored display applications.This work was supported by the European Commission through Nano CIS project (FP7-PEOPLE-2010-IRSES ref. 269279).Marí Soucase, B.; Singh, KC.; Moya Forero, MM.; Singh, I.; Om, H.; Chand, S. (2015). Synthesis and down conversion emission property of Eu3+ doped LaAlO3 CsAlO2 and LiLaO2 phosphors. Optical and Quantum Electronics. 47(7):1569-1578. https://doi.org/10.1007/s11082-014-9997-9S15691578477Abbattista, F., Vallino, M.: Remarks on the $$\text{La}_{2}\text{O}_{3}-\text{Li}_{2}\text{O}$$ La 2 O 3 - Li 2 O binary system between 750 and 1,000  $$^{\circ}$$ ∘ C. Ceram. 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Tuning the discharge potential of fluorinated carbon used as electrode in primary lithium battery

International audienceWhen the carbon lattice of the starting material exhibits a curvature as in the case of fullerenes and derivatives, the C-F bonding in the compounds resulting from the fluorination using molecular fluorine is strongly affected and the covalence is significantly weakened. 19F solid state NMR underlines that the higher the curvature the lower the C-F bonding covalence is. The electrochemical discharge potentials of these materials used as electrode in primary lithium batteries can be then tuned according to the curvature, i.e. the diameter of the outer tubes. The potential decreases from 2.9 to 2.3 V versus Li+/Li° according to the following classification: SWCNTs, MWCNTs and carbon nanofibres, which can be described as MWCNTs with large diameter due to the high number of walls. The case of highly fluorinated fullerenes is different because several types of bonding coexist and are progressively broken during the electrochemical process at potentials ranged in between 2.0 and 3.6 V. The behaviour of fluorinated nanocarbons is also compared to conventional graphite fluoride

New synthesis methods for fluorinated carbon nanofibres and applications

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Fluorinated nanocarbons using fluorinating agent: Strategies of fluorination and applications

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