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

Abstract

In this work, a series of Cr3+-doped A2NaYF6 (denoted as ANYF:Cr; A = K, Rb, Cs) fluoroyttrate double-perovskites with broad blue excitation and near-infrared (NIR) emission bands was fabricated using...

Near-infrared luminescence and high thermal stability of Rb2NaScF6:Cr3+ phosphor for spectroscopy applications

“…Considering the ionic radius and ionic charge between Na + (1.02 Å), Sc 3+ (0.745 Å) and Cr 3+ (0.615 Å) with the same coordination number, Cr 3+ is inclined to substitute the lattice site of Sc 3+ since the same valence state and the acceptable ionic radius difference. 26 This is also the reason why RNSF:0.03Cr has a shortened lattice parameter and a smaller unit cell volume than those of RNSF host.…”

Ultra-Broadband Near-Infrared Phosphors Realized by the Heterovalent Substitution Strategy

“…Transitionmetal ions such as Fe 3+ , Ni 2+ , and Cr 3+/4+ activated materials are another approach to meet NIR light requirements. 11,12 Owing to its d−d transition sensitivity in a crystal coordination environment, it presents a broad emission. 13−15 Among these transition metals, Cr 3+ its considered as an ideal activator for NIR emission with its d 3 electron configuration.…”

“…Luminescent glass activated by some rare-earth elements, such as Nd 3+ , Tm 3+ , and Yb 3+ , is the subject of early research on NIR phosphors. − However, these rare-earth-activated phosphors manifest a narrow emission band and low absorption due to the forbidden f–f transition. Transition-metal ions such as Fe 3+ , Ni 2+ , and Cr 3+/4+ activated materials are another approach to meet NIR light requirements. , Owing to its d–d transition sensitivity in a crystal coordination environment, it presents a broad emission. − Among these transition metals, Cr 3+ its considered as an ideal activator for NIR emission with its d 3 electron configuration. − By modulating the crystal field strength, a tunable NIR spectra can be realized. Although developing a Cr 3+ -based NIR phosphor is of great interest, achieving ultra-broadband NIR emission remains a significant challenge.…”

Ion Substitution Strategy toward High-Efficiency Near-Infrared Photoluminescence of Cs2KIn1–yAlyF6:Cr3+ Solid Solutions

“…In general, analysis of the XPS and SEM outcomes suggests that the strong interaction among Cr 3+ and F − has enhanced the crystallinity, thereby enabling the increase of the particle size, which may ultimately affect the emission intensity. 31,32…”

“…It is worth noting that changes in morphology may also be a factor in the change of luminescence characteristics. In general, analysis of the XPS and SEM outcomes suggests that the strong interaction among Cr 3+ and F – has enhanced the crystallinity, thereby enabling the increase of the particle size, which may ultimately affect the emission intensity. , …”