Engineering the optical properties of SrZrO3 crystals via Zn doping for superior passive daytime radiative cooling
Peer-Reviewed Publication
Welcome to theTsinghua University Press (TUP) News Page.
Below are the latest research news from TUP.
Updates every hour. Last Updated: 14-Dec-2025 20:11 ET (15-Dec-2025 01:11 GMT/UTC)
Passive daytime radiative cooling materials are promising for energy-free cooling as global energy consumption rises. SrZrO3 crystals, with their wide band gap and infrared photon lattice vibration absorption, are potential candidates for such applications. Most importantly, Zn doping has been shown to enhance both solar reflectivity and atmospheric window emissivity, which are critical for cooling performance. Despite the recognized potential of SrZrO3-based materials, the systematic understanding of how specific dopants like Zn synergistically modify the spectral radiative characteristics, and ultimately the passive cooling performance through combined effects on electronic structure, grain morphology, and lattice symmetry has yet to be comprehensively established. Filling this research gap is imperative for the rational design of high-performance radiative cooling materials.
The development of efficient electrocatalysts for saline water oxidation (SWO) is imperative for advancing seawater splitting technology to produce green hydrogen. In this work, a NiFe-Co2(OH)3Cl material was developed as pre-electrocatalyst for both active and stable SWO. During catalysis, the hydroxyloride was converted to oxyhydroxide with 35.4% enlarged ECSA, leading to the enhanced intrinsic activity (300 mV@10 mA cm-2, 49.9 mV decade-1). Moreover, the electrolyte Cl- would be incorporated to the catalyst lattice, thus improving the corrosion-resistance of the material, resulting in the high electrocatalytic stability for 100 h.
The utilization of blue lasers to excite phosphor materials holds great potential for the development of high-brightness laser-driven light sources. However, phosphor materials that can simultaneously constrain light spot expansion and enhance maximum luminous flux have been elusive, thereby limiting output luminance. This study presents a significant strategy to address the inherent trade-off between light spot confinement and luminous flux maximization in light sources through the design of core-cladding-like phosphor ceramics (CCPC) wafers. The YAG:Ce@Al2O3 CCPC wafer design effectively confines the light spot to an area as small as 0.53 mm2 while achieving an ultra-high luminance of 3900 lm·mm⁻2. This research presents a pioneering approach to the design of phosphor materials, targeting the realization of light sources with unprecedented luminance for broad frontier applications.
Microwave dielectric ceramics, as core materials for passive electronic components, are widely used in filters, dielectric antennas, and microwave communication systems. In high-frequency applications, ceramics with a low dielectric constant (εr) are preferred for their ability to reduce signal latency and simplify passive device fabrication. Ideal microwave dielectric ceramics should exhibit a near-zero temperature coefficient of resonant frequency (τf) and a high quality factor (Q×f, i.e., low dielectric loss tanδ = 1/Q). However, achieving ultra-low dielectric loss, high Q×f, and near-zero τf simultaneously remains a significant challenge. Olivine-type A2BO4 ceramics, with low εr (<10) and high Q×f (>100,000 GHz), offer exceptional low loss and high efficiency in high-frequency signal transmission, presenting broad prospects for next-generation wireless communications. Nevertheless, achieving a near-zero τf remains a critical challenge in this field.
Scientists have discovered that licorice extract, a common traditional herb, offers powerful protection against Paraclostridium bifermentans spores—a heat-resistant microbe that threatens the safety and shelf life of ready-to-eat (RTE) chicken breast. In laboratory tests, licorice extract concentrations above 12.5 mg/mL significantly suppressed spore growth, while a 50 mg/mL dose nearly doubled product shelf life at 15 and 20 °C. Predictive modeling confirmed the extract’s impact on microbial growth rates and lag phases. Moreover, treated chicken samples showed slower spoilage, with lower acidity and chemical breakdown. The findings open up new possibilities for natural, plant-based preservation strategies in the meat industry.
Egg yolk, long known for its nutritional benefits, may hold the key to a natural treatment for osteoporosis. A groundbreaking study has found that water-soluble egg yolk fractions, particularly the FC1 subfraction (< 3 kDa), significantly inhibit osteoclastogenesis—the process responsible for bone resorption. This discovery, based on in vitro tests with RAW264.7 macrophages, shows that FC1 not only curbs osteoclast formation but also activates apoptosis in mature osteoclasts. With further research, these egg yolk-derived bioactive compounds could pave the way for safer, natural supplements to promote bone health, offering an alternative to traditional treatments with fewer side effects.
Fermented sausages are renowned for their bold, region-specific flavors—but what truly drives these sensory profiles lies beneath the surface. This review uncovers how dynamic microbial successions shape flavor development in both Eastern and Western sausage varieties. While Western sausages such as salami and chorizo rely on controlled fermentation with selected starter cultures for consistency, Eastern sausages depend on spontaneous microbial activity and local ingredients, resulting in diverse and nuanced flavors. By revealing the biochemical and microbial pathways responsible for taste formation, the study offers new insights into improving quality, safety, and flavor optimization for global consumers.
As 5G deployment accelerates and 6G development begins, the demand for high-performance microwave dielectric ceramics (MWDCs) has surged. A team of researchers has developed a new garnet-type ceramic material, Y3MgAl3GeO12 (YMAG), with excellent microwave properties, including low permittivity, high quality factor, and good temperature stability. By optimizing the material with TiO2, they achieved near-zero temperature coefficient of resonant frequency, and a dielectric resonator antenna based on this material demonstrated outstanding performance in the X-band, highlighting its potential for 5G/6G applications.
Slow scintillation component due to charge carrier capture at point defects is a serious issue in scintillator materials. Therefore, the fabrication of scintillators with a high proportion of fast component in scintillation response is of great interest to material scientists. By applying the defect engineering strategy in the advanced optical Lu3Al5O12:Ce,Mg (LuAG:Ce,Mg) ceramics, ultrahigh fast scintillation proportion can be achieved with slight loss of the fast scintillation light. This strategy has a broad application potential in improving fast scintillation proportion of various oxide scintillators.
Transition metal diborides (TMB2) are materials of choice for the applications in hypersonic vehicles and scramjet engines due to their unique combination of fascinating properties such as high melting point, high elastic modulus, excellent thermal and chemical stability, etc. Understanding microscopic information such as the electronic structure and chemical bonding of TMB2 is essential for establishing the structure-property relationships. However, for decades, direct observation of atomic arrangements in TMB2 was seldom conducted due to the limited resolution of transmission electron microscope and filling this research gap was imperative. Herein the crystal structure and chemical bonding of CrB2 were approved for the first time using aberration corrected transmission electron microscopy coupled with electron energy loss spectroscopy (EELS) accessory. Combined with first-principles calculations based on density functional theory (DFT), CrB2 is confirmed to have an AlB2-type structure, where Cr bonds to each other in (001) plane by metallic bonding and B is bonding in the form of a graphite-like six-membered ring in (002) plane through sp2 hybridization, while Cr-B ionic-covalent bonding is formed in (110) plane. A detailed analysis of the experimental and calculated results of EELS of CrB2 show that the hybridization between Cr 3d and B has a significant effect on EELS of transition metal borides (TMB2). In addition, hysteresis loop of CrB2 was tested for the first time based on the theoretical calculation and the molar susceptibility of CrB2 was about 5.77×10-4 emu/mol.