Single-atom catalysts(SACs)have attracted extensive attention in the field of heterogeneous catalysis.However,the fabrication of SACs with high loading and hightemperature stability remains a grand challenge,especiall...Single-atom catalysts(SACs)have attracted extensive attention in the field of heterogeneous catalysis.However,the fabrication of SACs with high loading and hightemperature stability remains a grand challenge,especially on oxide supports.In this work,we have demonstrated that through strong covalent metal-support interaction,highloading and thermally stable single-atom Pt catalysts can be readily prepared by using Fe modified spinel as support.Better catalytic performance in N2O decomposition reaction is obtained on such SACs than their nanocatalyst counterpart and low-surface-area Fe2O3 supported Pt SACs.This work provides a strategy for the fabrication of high-loading and thermally stable SACs for applications at high temperatures.展开更多
Achieving electromagnetic wave scattering manipulation in the multispectral and broad operation band has been a long pursuit in stealth applications. Here, we present an approach by using single-layer metasurfaces com...Achieving electromagnetic wave scattering manipulation in the multispectral and broad operation band has been a long pursuit in stealth applications. Here, we present an approach by using single-layer metasurfaces composed of space-variant amorphous silicon ridges tiled on a metallic mirror, to generate high-efficiency dual-band and ultra-wideband photonic spin-orbit interaction and geometric phase. Two scattering engineered metasurfaces have been designed to reduce specular reflection;the first one can suppress both specular reflectances at 1.05–1.08 μm and 5–12 μm below 10%. The second one is designed for an ultra-broadband of 4.6–14 μm, which is actually implemented by cleverly connecting two bands of 4.6–6.1 μm and 6.1–14 μm. Furthermore, the presented structures exhibit low thermal emission at the same time due to the low absorption loss of silicon in the infrared spectrum, which can be regarded as an achievement of laser–infrared compatible camouflage.We believe the proposed strategy may open a new route to implement multispectral electromagnetic modulation and multiphysical engineering applications.展开更多
基金supported by the National Key Projects for Fundamental Research and Development of China(2016YFA0202801)the National Natural Science Foundation of China(21673226+3 种基金91645203 and 21590792)the “Transformational Technologies for Clean Energy and Demonstration”the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA21040200 and XDB17000000)supported by the Tsinghua Xuetang Talents Program
文摘Single-atom catalysts(SACs)have attracted extensive attention in the field of heterogeneous catalysis.However,the fabrication of SACs with high loading and hightemperature stability remains a grand challenge,especially on oxide supports.In this work,we have demonstrated that through strong covalent metal-support interaction,highloading and thermally stable single-atom Pt catalysts can be readily prepared by using Fe modified spinel as support.Better catalytic performance in N2O decomposition reaction is obtained on such SACs than their nanocatalyst counterpart and low-surface-area Fe2O3 supported Pt SACs.This work provides a strategy for the fabrication of high-loading and thermally stable SACs for applications at high temperatures.
基金National Natural Science Foundation of China(NSFC)(61575201,61622508,61822511)
文摘Achieving electromagnetic wave scattering manipulation in the multispectral and broad operation band has been a long pursuit in stealth applications. Here, we present an approach by using single-layer metasurfaces composed of space-variant amorphous silicon ridges tiled on a metallic mirror, to generate high-efficiency dual-band and ultra-wideband photonic spin-orbit interaction and geometric phase. Two scattering engineered metasurfaces have been designed to reduce specular reflection;the first one can suppress both specular reflectances at 1.05–1.08 μm and 5–12 μm below 10%. The second one is designed for an ultra-broadband of 4.6–14 μm, which is actually implemented by cleverly connecting two bands of 4.6–6.1 μm and 6.1–14 μm. Furthermore, the presented structures exhibit low thermal emission at the same time due to the low absorption loss of silicon in the infrared spectrum, which can be regarded as an achievement of laser–infrared compatible camouflage.We believe the proposed strategy may open a new route to implement multispectral electromagnetic modulation and multiphysical engineering applications.
