A conceptive design of self-adaptive photonic thermal management can keep cool under high temperature and keep warm under low temperature with the compound metasurface.

Oxygen vacancies (Ov) engineering has demonstrated tremendous power to expedite electrocatalytic kinetics for oxygen evolution reaction (OER). The mechanism is elusive, and most of them were attributed to the decoration or creation of active sites. Here, we report the critical role of superficial Ov in enhancing the electronic transport, thereby unfolding the catalytic potential of NiFe-layered double hydroxides for OER. We reveal that the superficial Ov engineering barely regulates the intrinsic catalytic activities but lowers the charge transport resistances by more than one order of magnitude. Loading-dependent electrochemical analysis suggests that the superficial Ov engineering intensively modulates the utilization rate of electronically accessible active sites for OER catalysis. By correlating catalytic activities to charging capacitances of C Φ (related to the absorption of reaction intermediates), we unveil a linear dependence, which indicates switchable catalysis on electronically accessible active sites. Based on the unified experimental and theoretical analysis of the electronic structures, we propose that the superficial Ov imposes electron donation to the conductive band of NiFeOOH, thereby enabling the regulation of electronic transport to switch on/off OER catalysis. The switch effect holds fundamental and technical implications for understanding and designing efficient electrocatalysts.

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Molybdenum disulfide (MoS2) has received widespread attention in recent years due to its exciting properties. However, the practical applications of MoS2 in optoelectronic devices are impeded by the power supply...

Lithium-ion capacitors (LICs) are promising energy-storage devices owing to their high energy densities and power densities that can well bridge the gap between lithium-ion batteries and supercapacitors. However, their energy-storage performance suffers from electrochemical capacity and kinetics imbalances between capacitor-type cathodes and battery-type anodes. Here, an electrode framework matching strategy is reported that can minimize these disparities between the counter electrodes. Based on a biomimic microphase separation mechanism, anode and cathode materials with the same interconnected mesoporous carbon framework but different assembled active sites have been fabricated. Due to the optimized integration of abundant active sites and functional electron/ion transport architectures in both electrodes, the assembled LICs deliver high energy densities up to 257 and 124 Wh kg −1 at power densities of 53 and 10 010 W kg −1 , respectively, exceeding previously reported LIC counterparts. The work provides a framework-based design strategy as well as a scalable fabrication method of nanostructured electrode materials toward high-performance LICs.

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Continuous development and advancement in modern detection technologies have increased the demand for multiband (e.g., visual and infrared) compatible camouflage. However, challenges exist in the requirements of incompatible structure resulting from the adaptation to different camouflage effects. This study is inspired by the light absorption structure of butterfly wing scales and demonstrates a porous anodic alumina/aluminum flake powder material prepared by a microscopic powder anodic oxidation technique for visual and infrared camouflage. The fabricated structures manipulate a compromise condition for visual camouflage by low reflectance (R̅ 400-800nm = 0.32) and dual-band infrared camouflage by low emission (ε ̅ 3-5μm = 0.081 and ε ̅ 8-14μm = 0.085). Further, the characteristic of short-range disorder in these bioinspired structures allows maintenance of the camouflage performance under omnidirectional detection (0−60°). This study provides new insight and a feasible method for coordinated manipulation of electromagnetic waves via bioinspired structural design and improved fabrication.