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Phosphors with intrinsic white light emission are of great potential in constructing high-quality white LEDs (WLEDs). In this work, we propose the use of energy transfer from Bi3+ to Eu3+ ions for white light emission. A unique Bi3+-activated phosphor LaGdO3 (LGO):Bi3+ was generated using the conventional high-temperature solid-state process. An energy transfer was established by introducing Eu3+ into the phosphor composition. The emission colour of LGO:Bi3+,Eu3+ phosphors changes from cyan to white to orange-red depending on the Bi3+/Eu3+ doping proportion. The energy transfer between the Bi3+ and Eu3+ ions results from the dipole–dipole interaction. The LGO:Bi3+,Eu3+ phosphors were combined with a near-ultraviolet chip to successfully create a single-component WLED device with a colour-rendering index of 92.4. Our work demonstrates the energy transfer as a route for single-component white light emission and makes LGO:Bi3+,Eu3+ phosphors one of the candidate materials for near-ultraviolet lighting. [ABSTRACT FROM AUTHOR]

Broadband near-infrared phosphors have received unprecedented attention in areas such as non-destructive food testing, plant growth light sources, night vision lighting, and medical diagnostics. It is challenging to design phosphors with significant full-width at half-maximum (FWHM) width variations. In this work, Sr3SiAl10O20:Cr3+ (SSAO:Cr3+) has two emission centers and achieves an interesting change of emission peaks from the ultra-narrow band (FWHM = 37 nm) to ultra-wideband (FWHM = 225 nm) with increasing Cr3+ doping concentration. Photoluminescence decay lifetime fitting confirms the existence of energy transfer in two emission centers. The emission intensity and thermal stability of the phosphor after 950 nm were extended by introducing Yb3+ ions. A NIR phosphor-converted LED was fabricated using SSAO:Cr3+,Yb3+ and a 410 nm LED chip, which shows great potential in the fields of night vision illumination, non-destructive monitoring, and information encryption. [ABSTRACT FROM AUTHOR]

Molecular dynamics (MD) technology can be used to explore the properties of films made by mixing protein and starch. MD explains the conformation of atoms and molecules at the microscopic level that cannot be observed with the naked eye, and can provide information such as the hydrogen bond force, electrostatic force, van der Waals force, Coulomb force, and chemical bond energy between protein and starch at a certain state, which is helpful for researchers to understand or develop new materials. This review focused on protein-starch edible films, microwave heating (MH), MD principle and applications, and analyzed the research status and correlation between protein, starch and protein-starch films and microwave heating. MD technology further reveals the microstructure changes and mechanism of protein-starch based materials under MH environment, which can provide reference for the development and utilization of protein-starch based films. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) printing provides a new method for innovative processing of shrimp surimi. However, there still exists a problem of uneven discharge during the 3D printing of surimi. The effects of different amounts of lard oil (LO), soybean oil (SO), and olive oil (OO) (0%, 2%, 4%, and 6%, respectively) added to shrimp surimi on the 3D printability of surimi were evaluated. The findings showed that with the increase in the added oil, the rheological properties, texture properties, water-holding capacity (WHC), and water distribution of surimi with the same kind of oil were significantly improved; the printing accuracy first increased and then decreased; and the printing stability showed an increasing trend (p < 0.05). The surimi with 4% oil had the highest printing adaptability (accuracy and stability). Different kinds of oil have different degrees of impact on the physical properties of surimi, thereby improving 3D-printing adaptability. Among all kinds of oil, LO had the best printing adaptability. In addition, according to various indicators and principal component analysis, adding 4% LO to shrimp surimi gave the best 3D-printing adaptability. But from the aspects of 3D printing properties and nutrition, adding 4% SO was more in line with the nutritional needs of contemporary people. [ABSTRACT FROM AUTHOR]

In this work, a series of BaSrGd4O8:xBi3+ blue phosphors was synthesized employing the high-temperature solid-state method. Phase purity of the samples was verified by X-ray diffraction and Rietveld refinement. Time-resolved photoluminescence spectra revealed the existence of two distinct Bi sites. Subsequent optimization of dopant types and doping levels in the batch led to an almost twofold increase in quantum efficiency. The introduction of Eu3+ into the phosphors facilitated the construction of an energy transfer pathway. As the concentration of Eu3+ was increased, the emission color changed from blue to purple and finally to red. In addition, the thermal stability and potential applications of the phosphors were extensively investigated. Finally, two WLED devices were successfully fabricated with color rendering indices of 96.27 and 92.18, and correlated color temperatures of 5198 and 2475 K. This underscores the prospective application of these phosphors in the field of high-quality warm WLEDs. [ABSTRACT FROM AUTHOR]

Crystal‐field engineering can obtain targeted emission more effectively, compared with the laborious experimental screening of new hosts. However, there still lack of paradigms for obtaining Ce3+‐doped cyan phosphors by crystal‐field engineering, and the correlation between the emission and the local structure of the Ce3+ ions has rarely been disclosed. Herein, through substituting the K+ in K3‐yRbyGdSi2O7:Ce3+ with Rb+, the emission color changes from yellow‐green to cyan and finally to blue. In addition, the emission intensity and thermal stability greatly improve, as the internal quantum efficiency increases from 39.4% (y = 0) to 83.6% (y = 1.2), and the thermal activation energy increases from 0.25 eV (y = 0) to 0.36 eV (y = 1.2). The optimized luminescent properties have been interpretated from the change in energy level splitting and configuration coordinate of Ce3+, both of which originate from the elongated Ce3+─O2− bonds. Finally, the cyan‐emitting phosphor K1.8R1.2GSO:Ce3+ is applied to bridge the cyan gap in a fabricated white light‐emitting diodes, and the color rendering index is improved from 90.8 to 93.4. This work not only provides an efficient cyan phosphor, but also highlights an avenue for the rational design of phosphors with optimal luminescent properties. [ABSTRACT FROM AUTHOR]