Near-Infrared Broadband ZnTa₂O₆:Cr³⁺ Phosphor for pc-LEDs and Its Application to Nondestructive Testing

Abstract

Broadband near-infrared (NIR) phosphors are necessary materials for developing portable NIR light sources. Moreover, exploiting an NIR phosphor with a main peak located beyond a wavelength of 900 nm remains a challenge because this spectral range has great potential in biological nondestructive testing and solution testing. In this study, a range of Cr 3+ -doped ZnTa 2 O 6 (ZTO) phosphors were completely synthesized by a solid-state method, which show broadband Cr 3+ emission centered at 935 nm with a large full width at half maximum (FWHM) of 185 nm due to two distorted octahedral sites. A packaged phosphor-converted light-emitting diode (pc-LED) device is used to penetrate a 5-cm-thick chicken breast and identify diverse solutions based on differences in the measured transmission spectra. The results indicate broad application prospects in the field of biological tissue penetration and solution analysis.

An Efficient Perovskite‐Like Phosphor with Peak Emission Wavelength at 850 nm for High‐Performance NIR LEDs

“…Though the above NIR phosphors have high IQE and excellent thermal stability, they also suffer from deficient emission in 850-1100 nm, which limits their practical applications. Some NIR phosphors with longer wavelength emission (>850 nm), such as La 3 Ga 5 GeO 14 :Cr 3+ (920 nm), [26] ZnTa 2 O 6 :Cr 3+ (935 nm), [27] and LiIn 2 SbO 6 :Cr 3+ (965 nm), [28] were reported, but their IQEs are Near-infrared (NIR) phosphor-converted light-emitting diodes (pc-LEDs) are an emerging light source demanded for the miniaturization of NIR spectroscopy. However, the photoelectric efficiency and spectral properties of NIR pc-LEDs are still very limited due to a lack of efficient broadband NIR phosphors with peak emission wavelength >850 nm.…”

Enhanced and Broadened NIR Emission of CaZnGe2O6:Cr3+ by Yb3+ Codoping for NIR Applications

“…Figure a shows the transmission spectra of the pc-LED prepared with CZG:2Cr,0.75Yb through glucose solutions with different concentrations and obvious absorption can be observed around 850 and 1010 nm. The absorption around 850 nm can be ascribed to the combined absorption of third and fourth frequency multiplication of C–H bonds, and the absorption around 1010 nm originates from the second overtones of O–H bonds. − The concentration of glucose solution can be estimated with the absorption intensity of the C–H bond around 850 nm based on Lambert–Beer law: A = log I 0 I = ε b c here A is the absorbance, I 0 and I are the initial intensity and the transmission spectral intensity through glucose, ε is the molar absorption coefficient of the component, b is the optical path, and c is the concentration of the component to be measured. Figure b depicts the absorbance vs glucose concentration, and the correlation coefficient reaches 0.985.…”

Strategy to probe multimodal light emissions from Eu3+/Yb3+activated garnet nanophosphors for LED devices and solar cell applications

“…The red emitting sample could be used as a red-emitting component for WLEDs 17,54 to achieve a high color rendering index (CRI) and low CCT values, and the NIR/red emitting sample could be utilized for biological non-destructive testing, food analysis, night vision and so on. 55,56…”

“…The red emitting sample could be used as a red-emitting component for WLEDs 17,54 to achieve a high color rendering index (CRI) and low CCT values, and the NIR/red emitting sample could be utilized for biological non-destructive testing, food analysis, night vision and so on. 55,56 3.6.2 Possible application in c-Si solar cells. It has been observed that the spectral region 900-1100 nm is the most efficient working spectral area for c-Si solar cells, and it shows a weak response towards the short-wavelength region because of thermal loss mainly in the 300-500 nm region where the solar irradiation is quite good.…”