Journal of Advanced Materials Research | Volume 2, Issue 4: 285-298, 2026 | DOI: 10.62762/JAMR.2026.189146
Abstract
Garnet-structured fluoride phosphors are attractive for phosphor-converted near-infrared light-emitting diodes (NIR pc-LEDs) owing to their broadband emission and thermal stability. Herein, pure-phase Na$_3$Al$_{2-x}$Cr$_x$Li$_3$F$_{12}$ (x = 0--0.16; NALF:Cr$^{3+}$) phosphors were synthesized hydrothermally, and their structure, morphology, crystal field, and luminescence were systematically investigated. Crystal-field analysis yielded a Dq/B of $\sim$2.18, confirming a weak crystal-field environment for Cr$^{3+}$. Under 430 nm excitation, all samples show a broad NIR band over 650--900 nm with a FWHM of $\sim$101 nm, ascribed to the $^4T_{2g}\rightarrow{}^4A_{2g}$ transition. Fluorescence... More >
Graphical Abstract