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

Abstract

The rapid development of minimized near-infrared (NIR) phosphor-converted LEDs (pc-LED) has evoked a large demand for broadband NIR phosphors and will enable breakthrough NIR spectroscopy applications. Consequently, the search for...

Sharp-Line Near-Infrared Emission from Tetrahedron-Occupied Ni2+ in Ca2GeO4

“…The average lifetimes of Ca 2 GeO 4 : x Ni 2+ were calculated as 300.54, 303.78, 309.59, 319.37, 294.54, 276.26, 262.75, and 184.35 μs for x = 0.001, 0.003, 0.005, 0.007, 0.01, 0.02, 0.03, and 0.04, respectively. These are of similar scale with reported Ni 2+ /Mn 5+ -activated phosphors (MgTi 2 O 5 :Ni 2+ : ∼510 μs and Ba 3 (VO 4 ) 2 :Mn 5+ : ∼381 μs), which are characteristic for 3 d –3 d transitions.…”

“…Thus, the sample with the highest PLQY is the sample with the optimized concentration (x = 0.01) were calculated as 300.54, 303.78, 309.59, 319.37, 294.54, 276.26, 262.75, and 184.35 μs for x = 0.001, 0.003, 0.005, 0.007, 0.01, 0.02, 0.03, and 0.04, respectively. These are of similar scale with reported Ni 2+ /Mn 5+ -activated phosphors (MgTi 2 O 5 :Ni 2+ : ∼510 μs 26 and Ba 3 (VO 4 ) 2 :Mn 5+ : ∼381 μs 27 ), which are characteristic for 3d−3d transitions. Apart from QE, thermal stability is another indispensable factor that dedicates the practical applications of phosphors.…”

Boosting broadband short-wave infrared emission to achieve near-unity quantum efficiency via bridging Cr3+–Ni2+ in spinel solid-solutions towards light-emitting diode applications

“…Short-wave infrared (SWIR) light holds great practical potential in night vision, non-invasive bioimaging, optical communication, health monitoring, and nondestructive testing and analysis, due to its unique electromagnetic wave features, such as invisibility to the human eye, tissue penetration, and intrinsic interaction with certain chemical groups. [1][2][3][4][5][6][7][8][9][10][11][12] Commercially available SWIR light sources have their own inevitable drawbacks. For example, semiconductor-based SWIR light-emitting diodes (LEDs) show an extremely narrow FWHM of their emission spectrum.…”

Valence state control of Cr4+-activated Li2SrGeO4for NIR-II light source to distinguish deuterium and non-deuterium reagents

“…16–19 However, the luminescence efficiency of Bi x + ( x < 3) ion-activated phosphors is not high enough and the Ni 2+ -activated material can only be excited by near-ultraviolet light. 20–23 Compared with Cr 3+ , the optimal excitation wavelength of Cr 4+ does not match well with the blue chip, which limits its application in blue LED-based NIR pc-LED. However, as LED packaging technology matures, vertical LEDs become potential candidates for LED applications owing to their higher power and higher current compared to conventional lateral LEDs.…”