A simple and generic post-treatment strategy for highly efficient Cr³⁺-activated broadband NIR emitting phosphors for high-power NIR light sources

Abstract

Cr3+-activated broadband near-infrared (NIR) emitting phosphors have attracted more attention worldwide as they are strongly expected to be promising light convertors for phosphor-converted NIR light sources for NIR spectroscopy and...

Ni2+-activated MgTi2O5 with broadband emission beyond 1200 nm for NIR-II light source applications

“…In previous reports, research on NIR phosphors for NIR-LEDs is mainly focused on trivalent rare earth (RE) ions (Tm 3+ , Pr 3+ , and Nd 3+ ); [10][11][12][13] however, RE-activated phosphors have certain drawbacks such as low efficiency and a narrow excitation/emission bandwidth, which hinder their application for NIR-II pc-LEDs. 14,15 Cr 3+ and Eu 2+ doped phosphors are another research hotspot in the field of inorganic NIR luminescent materials, 3,[16][17][18] such as X 3 Sc 2 Ga 3 O 12 :Cr (X = Lu, Y, Gd, and La) (from 600 to 1000 nm), 19 CaAlSiN 3 :Eu 2+ (from 500 to 800 nm), 20 and K 3 ScSi 2 O 7 :Eu 2+ (from 600 to 1100 nm). 16 However, the Cr 3+ and Eu 2+ -activated phosphors generally have a relatively short emission wavelength (o1100 nm) and deficiency in longer emission, especially above 900 nm.…”

“…16 However, the Cr 3+ and Eu 2+ -activated phosphors generally have a relatively short emission wavelength (o1100 nm) and deficiency in longer emission, especially above 900 nm. 16,18 Based on the above, a phosphor with NIR-II (1000-1700 nm) emission is much more required as a key point for NIR-II pc-LED applications to obtain valuable imaging and analysis information. Unlike traditional luminescent metal ions, Ni 2+ with an electronic configuration of 3d 8 usually shows innate broadband NIR-II emission when it is located in octahedral sites.…”

“…16 However, the Cr 3+ and Eu 2+ -activated phosphors generally have a relatively short emission wavelength (<1100 nm) and deficiency in longer emission, especially above 900 nm. 16,18…”

High efficiency near-infrared light emission and ultra-high stability of the lead-free double perovskite Cs2Na1−xAgxBi1−yAlyCl6

“…There are many kinds of NIR light emitters. [55][56][57] In Table S2 (ESI †), [58][59][60][61][62][63][64][65][66] we provide a comparison of a Cr-doped metal oxide and CuInSe 2 with our work. Cr-doped metal oxides have been widely reported due to their high quantum efficiency and thermal stability, but their emission width is not enough to cover the first region of 650-900 nm, and carcinogenic Cr 6+ will be generated when preparing Cr-doped phosphors.…”

Near-infrared Sr7NaGa(PO4)6:Cr3+,Ln3+ (Ln = Nd, Er, and Yb) phosphors with different energy transfer paths: photoluminescence enhancement and versatility

“…Near-infrared (NIR) phosphors with emission in the range of 700-1700 nm have drawn widespread attention because of their unique, versatile luminescent properties and exciting application prospects. [1][2][3][4] NIR phosphor-converted LEDs (NIR pc-LEDs) are expected to be the next generation NIR light source due to their small size, high conversion efficiency, long lifetime, and environmental friendliness. 5,6 The NIR pc-LEDs with broadband NIR emission can be employed in some areas such as nondestructive analysis and night vision.…”