Recent advances in high-entropy alloys have spurred many breakthroughs in the fields of high-temperature materials and optical materials and they provide incredible application potentialities for photothermal conversion systems. Solar-selective absorbers (SSAs), as key components, play a vital role in photothermal conversion efficiency and service life. The most pressing problem with SSAs is their inconsistent optical performance, an instability constraint induced by thermal stress. A feasible method of improving performance stability is the introduction of high-entropy materials, such as high-entropy alloy nitrides. In this study, enabled by an intrinsic MoTaTiCrN absorption layer, the solar configuration achieves greatly enhanced, exceptional thermotolerance and optical properties, leading to the formation of a scalable, highly efficient, and costeffective structure. Computational and experimental approaches are employed to achieve optimum preparation parameters for thicknesses and constituents. The crystal structure of high-entropy ceramic MoTaTiCrN is fully investigated, including thicknessdependent crystal nucleation. High-temperature and long-term thermal stability tests demonstrate that our proposed SSA is mechanically robust and chemically stable. Moreover, a low thermal emittance (15.86%) at 500 °C promotes the photothermal conversion efficiency. In addition, due to the exceptional spectral selectivity (α/ε = 92.3/6.5%), thermal robustness (550 °C for 168 h), and photothermal conversion efficiency (86.9% at 550 °C under 100 sun), it is possible for our proposed SSA to enhance the practical realization of large-area photothermal conversion applications, especially for concentrated solar power systems.

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Due to the low reactivity of 1,6‐dienes and the challenge of selectively differentiating such two olefins, the development of metal‐catalyzed asymmetric cyclization of 1,6‐dienes remains largely underdeveloped. Herein, we describe the first copper(I)‐catalyzed asymmetric borylative cyclization of cyclohexadienone‐tethered terminal alkenes (1,6‐dienes) via a tandem process: the regioselective borocupration of the electron‐rich terminal alkene and subsequent conjugate addition of stereospecific secondary alkyl‐copper(I) to the electron‐deficient cyclohexadienone, affording enantioenriched bicyclic skeletons bearing three contiguous stereocenters in all cis‐form. Meanwhile, this mild catalytic protocol is generally compatible with a wide range of functional groups, which allows further facile conversion of the cyclization products.

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Developing advanced materials with a high-entropy concept is one of the hot trends in materials science. The configurational entropy of high-entropy materials can be tuned by introducing different atomic species, which can also impart a result in excellent physical and chemical properties. In this work, we synthesized a solid-solution oxide (Cu, Mn, Fe, Cr) 3 O 4 by a simple and scalable solid-phase synthesis method. We extensively investigated the microstructure and chemical composition, indicating that (Cu, Mn, Fe, Cr) 3 O 4 has a single-phase spinel structure. Simultaneously, we reasonably evaluated the position occupied by the elements of (Cu, Mn, Fe, Cr) 3 O 4 in a spinel structure as (Cu 0.75 Fe 0.25 )(Fe 0.25 Cr 0.375 Mn 0.375 ) 2 O 4 . Here, we first evaluated the infrared radiation performance of (Cu, Mn, Fe, Cr) 3 O 4 . The new, high-entropy oxide (HEO) (Cu, Mn, Fe, Cr) 3 O 4 powder exhibits high infrared emissivity values of 0.879 and 0.848 in the wavelengths of 0.78−2.5 and 2.5−16 μm, respectively, and has excellent thermal stability. More importantly, the infrared emissivity values of as-prepared HEO coating reach 0.955 (0.78−2.5 μm) at room temperature and 0.936 (3−16 μm) at 800 °C. This work provides a viable strategy toward the laboratory mass production of this HEO for infrared radiation materials, which shows great potential in the energy-related applications.

Passive daytime radiative cooling (PDRC) is an emerging energy-free cooling technology, which can weaken our dependence on air-conditioning requirements with energy-consuming. Though the advance in photonic micro/nanostructures PDRC materials achieves...