Crystal-Field Engineering Control of an Ultraviolet-Visible-Responsive Near-Infrared-Emitting Phosphor and Its Applications in Plant Growth, Night Vision, and NIR Spectroscopy Detection

Broadband near-infrared (NIR) phosphor-converted light-emitting diodes (pc-LEDs) have many prospective applications in areas related to food inspection, health management, plant growth, and night vision, because NIR phosphors are critical components of the corresponding devices. Given the wide-ranging applicability of the material, this study is designed to comprehensively evaluate a series of novel NIR phosphors: BaMgGaxAl10-xO17:Cr3+ (x = 0, 1, 2, 3). The ultra-low-temperature (4 K) fluorescence spectroscopy and decay curve results confirm that Cr3+ occupies the four lattice sites of Al3+ in the matrix. Additionally, the introduction of Ga3+ increases the full-width at half-maximum (FWHM) of the NIR spectrum from 100 to 300 nm without affecting the fluorescence efficiency; it also considerably increases spectral coverage. An experiment to evaluate the applicability of the novel NIR phosphors reveals that the sunlight-converting film prepared by applying the material combination of BaMgGa3Al7O17:0.02Cr(3+) is able to effectively promote the growth of Chlorella. In addition, the NIR pc-LED with a BaMgGa3Al7O17:0.2Cr(3+) basis and 395-nm LED chip has been proven to be an excellent candidate for applications in NIR spectral detection and night-vision technology.

Automated summary

This study comprehensively evaluates broadband near-infrared (NIR) phosphors with wide-ranging applications in food inspection, health management, plant growth, and night vision. The introduction of Ga3+ in the NIR phosphors increases the spectral coverage and significantly improves the full-width at half-maximum (FWHM) of the NIR spectrum. Experiments demonstrate that a sunlight-converting film made with BaMgGa3Al7O17:0.02Cr(3+) promotes the growth of Chlorella, while a NIR pc-LED based on BaMgGa3Al7O17:0.2Cr(3+) and a 395-nm LED chip shows promise for NIR spectral detection and night-vision technology.