Color Tuning of Direct White Light of Lanthanum Aluminate with Mixed-Valence Europium

Abstract

The generation of direct white-light emission of the coexisting valence-varied europium-lanthanum aluminate through substitution of cations into the host and its resultant adjustment of the energy transfer have been presented. With respect to La(0.99-x)Sr(x)AlO(3-delta):Eu(0.01) and La(0.994)Al(1-x)O(3-delta):Eu(0.006), and Mn(x), Li(0.012), the green-light emission positioned at 515 nm plays a key role to color mix for white light and can be efficiently tuned by adjusting the transfer of energy and relevant transition emissions between the luminous centers of Eu(2+) and Eu(3+)/Mn(2+), via varying amounts of dopants. Direct white-light emission with optimized values of 86 for the color rendering index and 5091 K for the correlated color temperature has been achieved for lanthanum aluminate by this mixed-valence means.

Investigation of 515nm green-light emission for full color emission LaAlO3 phosphor with varied valence Eu

“…Except that blue emission band positioned at around $ 445 nm for the 5d-4f transition emission of Eu 2+ and red emission peaks positioned at $ 592 and $618 for the 5 D 0 -7 F 1,2 transition emission of Eu 3+ [18][19], we found that green emission at around $ 515 nm plays a key role to mix white light for our explored material. The luminescence mechanism for this green emission, however, is fuzzy and need to be clarified for this mixvalence Eu co-doped LaAlO 3 phosphor.…”

Growth and optical spectroscopy of KPb2Cl5 crystal containing Mn2+

“…The electronic absorption, excitation and emission spectra of Mn 2+ have been extensively investigated in a wide variety of hosts [25][26][27][28][29][30][31][32][33][34]. As far as the emission color of Mn 2+ activated phosphors is concerned, it falls into two classes: those with green emission and those with green-to-red emission [35,36].…”

Princípios fundamentais e modelos de transferência de energia inter e intramolecular

“…Outra área de aplicação da teoria de Förster se encontra na utilização de quantum dots semicondutores como sondas de processos biológi-cos. 6 O modelo de Dexter se aplica especialmente a sistemas onde a distância de transferência é muito curta e onde há sobreposição orbital entre as espécies envolvidas apresentando, assim, conjugação. 7 Um exemplo recente é o apresentado por Mao e Wang, 8 que confirmaram o mecanismo de transferência de energia para um fósforo à base de aluminato de lantânio codopado com manganês(II) e európio(III).…”