Through coordination of the Seebeck coefficient and carrier concentration in Cu3SnS4, TE performance improves significantly with the ZT value of 0.75 at 790 K.

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light in this range is known as the first biological window, and the NIR radiation can effectively penetrate biological tissues, which means that a non-destructive and non-invasive diagnosis of the human physiological state can be performed by a perceptible penetration depth in biological tissues. [6] For plant cultivation, red/ photosensitive pigments (PR) and far-red/ photo sensitive pigments (PFR), two pigments indispensable for plant growth, have a specific absorption in the NIR region, and PFR has a strong absorption peak at 730 nm. [7] Various NIR-emitting materials have been developed for halogen lamps, lightemitting diodes (LEDs), organic LEDs (OLED), and phosphor-converted LEDs (pc-LEDs). Among them, halogen lamps have continuous ultra-broadband spectral properties from visible to NIR, but their low luminous efficiency, high operating temperature, and long response time limit their applications. [8] NIR LEDs overcome most of the drawbacks of halogen lamps, but the narrow fullwidth at half maximum (FWHM) and the LED arrangement luminous unevenness also severely limit their utilization at scale. [9] OLEDs are disappointing in terms of efficiency or temperature resistance, even though they have good applicability. [10] The most suitable solution may be the development of NIR pc-LEDs combining InGaN blue LED chips with broadband NIR phosphors. It satisfies both the ultra-broadband spectral emission and the requirements of compactness, efficiency, portability, and low cost. [11] For this purpose, broadband NIR phosphors that are well matched to the blue LED chips need to be developed.Many NIR broadband phosphors based on inorganic matrixdoped activators have been reported so far, [12] however, most of them have disadvantages such as unsuitable NIR emission wavelength, unstable emission intensity at high temperature, and low luminescence efficiency, which greatly limit their applications in various fields. Cr 3+ ions exhibit broadband absorption in the ultraviolet-visible spectral range, which stems from its unique 3d 3 electronic structure. [13] In addition, Cr 3+ ions can display tunable narrowband or broadband spectrum from 600-1600 nm, depending on whether they are in a strong or weak Broadband near-infrared (NIR) phosphor-converted light-emitting diodes (pc-LED) are ideal light sources to meet the next generation of NIR spectroscopy. However, NIR phosphors have numerous problems such as low quantum yields (QY) and low thermal stability. In this work, a series of Gd 3 Y x In x Ga 5-2x O 12 :Cr 3+ NIR broadband phosphors with high internal quantum yields (IQYs) and high thermal stability are discovered by uniquely replacing GaO 6 in Gd 3 Ga 5 O 12 with Y 3+ and In 3+ in a co-doped manner through cation modulation. Under 449 nm excitation, Gd 3 Y 0.5 In 0.5 Ga 4 O 12 (GYIG):yCr 3+ depicts emission from 650 to 1050 nm with a full-width at half maximum (FWHM) of 134 nm. The emission intensity reaches its optimum value at y = 6%, while the IQY reaches an impressive 81.8% and, at 375 K, the emission intensity r...

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.