Multi-color luminescence of Sm3+ -doped Na2 YMg2 V3 O12 phosphor potentially applicable in white-LEDs.

Abstract

A novel multi-color emitting Na2 YMg2 V3 O12 :Sm3+ phosphor was synthesized using a solid-state reaction, and its crystal structure, luminescence properties, and thermal stability were studied. Charge transfer within the (VO4 )3- groups in the Na2 YMg2 V3 O12 host led to a broad emission band between 400 and 700 nm, with a maximum at 530 nm. The Na2 Y1-x Mg2 V3 O12 :xSm3+ phosphors exhibited a multi-color emission band under 365 nm near-ultraviolet (near-UV) light, consisting of the green emission of the (VO4 )3- groups and sharp emission peaks at 570 nm (yellow), 618 nm (orange), 657 nm (red), and 714 nm (deep red) of Sm3+ ions. The optimal doping concentration of Sm3+ ions was found to be 0.05 mol%, and the dipole-dipole (d-d) interaction was primarily responsible for the concentration quenching phenomenon. Using the acquired Na2 YMg2 V3 O12 :Sm3+ phosphors, commercial BaMgAl10 O17 :Eu2+ blue phosphor, and a near-UV light-emitting diode (LED) chip, a white-LED lamp was designed and packaged. It produced bright neutral white light, manifesting a CIE coordinate of (0.314, 0.373), a color rendering index (CRI) of 84.9, and a correlated color temperature (CCT) of 6377 K. These findings indicate the potential of Na2 YMg2 V3 O12 :Sm3+ phosphor to be used as a multi-color component for solid-state illumination.