Ultraintense Zero-Phonon Line from a Mn⁴⁺ Red-Emitting Phosphor for High-Quality Backlight Display Applications

Abstract

The zero-phonon line (ZPL) of Mn4+, which highly depends on its local environment, is usually much weaker than the vibrational phonon sidebands. In this work, an ultraintense ZPL emission, coming from a brand new red-emitting Rb2LiGaF6:Mn4+ (RLGFM) phosphor upon blue light excitation, is presented. The interesting spectral characteristic originates from the nonequivalent substitution of Mn4+ for Ga3+ in a rigid octahedral structure with a low symmetry, which induces neighboring cation vacancies that distort the local symmetry of the [MnF6] octahedra. Benefiting from the ultraintense ZPL emission, a wide color gamut is achieved using RLGFM and β-SiAlON:Eu2+ as color converters. Moreover, a comprehensive investigation on the thermal quenching behavior is also conducted to provide detailed insights to explore novel Mn4+ red phosphors for high-quality backlight display applications.

Cationic pair substitution in LaAlO3:Mn4+ for octahedral-tilting-dependent zero-phonon line

“…S3 and S4† show the fluorescence decay curves corresponding to Mn 4+ in the LBAT:0.001Mn 4+ ( x = 0–0.2) and LYAG:0.001Mn 4+ ( y = 0–0.2) phosphors under excitation at 340 nm, as monitored at 726 nm at room temperature and at 77 K. All decay curves are found to be well fitted by a single exponential function, suggesting the single site occupancy of the Mn 4+ in the host lattice. It is expressed as follows: 34 where I t and I 0 are the luminescence intensities at time t and 0. A refers to a constant and τ represents the exponential component of the decay time.…”

Luminescence properties of Cr3+-doped near-infrared emissive fluoroyttrates for light-emitting diodes

“…23 The refinement parameters of KNYF:0.10Cr ( R wp = 8.98%, R p = 6.85%, and χ 2 = 0.780), RNYF:0.10Cr ( R wp = 6.17%, R p = 4.48%, and χ 2 = 2.232) and CNYF:0.10Cr ( R wp = 5.59%, R p = 4.36%, and χ 2 = 1.536) indicate that the refined results are dependable. 24 According to the crystallographic information files created by the GSAS program, the general structural diagram is built and displayed in Fig. 1b, in which the A, Na and Y cations have only one lattice site with 12-, 6- and 6-fold coordination, respectively.…”

“…The bandgaps and electronic structures of the ANYF hosts were calculated with the Vienna ab initio simulation package based on density functional theory (DFT). 24 The generalized gradient approximation with the Perdew–Burke–Ernzerhof functional was adopted as the exchange–correlation potential.…”

A novel red phosphor Cs2NaGaF6:Mn4+ with ultra-strong zero-phonon lines and long wavelength phonon sidebands for high-quality WLEDs

“…Furthermore, the larger emission wavelength of the υ 6 vibration peak can be explained by the coordination environment of Mn 4+ . Similar to a series of A 2 BAlF 6 :Mn 4+ (A,B = Rb, Cs, K, Ns, Li; B = Al, Sc, Ga) red phosphors, such as K 2 LiAlF 6 : Mn 4+ , 32 Rb 2 LiGaF 6 :Mn 4+ , 33 Cs 2 NaAlF 6 :Mn 4+ (ref. 26) and K 2 LiGaF 6 :Mn 4+ , 34 the matrix structure of Cs 2 NaGaF 6 :Mn 4+ has a [NaF 6 ] octahedron at the B site, and [NaF 6 ] and [MnF 6 ] share three F atoms.…”