A Super‐Broadband NIR Dual‐Emitting Mg2SnO4:Cr3+,Ni2+ Phosphor for Ratiometric Phosphor‐Converted NIR Light Source Applications

Abstract Near‐infrared (NIR) phosphor‐converted light‐emitting diodes (pc‐LEDs) have sparked tremendous interest in NIR spectroscopy. However, conventional NIR pc‐LEDs with a narrow full‐width at half‐maximum (FWHM) and single‐emission block the detection scope and detection accuracy for NIR spectroscopy analysis. Herein, a multicenter strategy is developed for the preparation of blue‐light‐excitable Mg 2 SnO 4 :Cr 3+ ,Ni 2+ phosphors with NIR dual‐emission (λ em = 830/1480 nm, total FWHM = 532 nm). Benefiting from the unique NIR dual‐emission, a ratiometric measurement system with a self‐calibration function is established for highly precise and nondestructive detection. For the first time, a good linear relationship with a detection limit of 0.22 wt.% is achieved for quantitative, non‐invasive detection of water/ethanol mixtures in the field of NIR spectroscopy applications. Additionally, a super‐broadband pc‐LED with a NIR output power of 16.1mW@300 mA is fabricated, demonstrating its applications in high‐penetration imaging and anticounterfeiting. These results provide an approach to achieving NIR dual‐emission phosphor, thereby opening a new avenue for exploring ratiometric NIR spectroscopy techniques.