Semiconductor materials with roughened surfaces offer great advantages for surface enhanced Raman spectroscopy(SERS)based on a chemical enhancement mechanism.Herein,M(OH)_(x)(M=Fe,Co,Ni)hollow octahedral microcages ar...Semiconductor materials with roughened surfaces offer great advantages for surface enhanced Raman spectroscopy(SERS)based on a chemical enhancement mechanism.Herein,M(OH)_(x)(M=Fe,Co,Ni)hollow octahedral microcages are synthesized and explored as novel SERS-active substrates for sensitive dye molecule detection.A single as-prepared hollow M(OH)x micro-octahedron particle with hierarchical surface architecture can be used as a highly sensitive SERS platform without interference from the surrounding environment.A comparative study indicates that Ni(OH)_(2) microcages can provide optimal Raman enhancement of various dye molecules with an enhancement factor of up to 2.35×10^(3),due to stronger coupling interactions between the dye molecule and metal center,which greatly facilitate the electron transfer process.This work can expand the availability of SERS substrates with higher sensitivity and stability,and focus more attention on an in-depth understanding of chemical enhancement mechanisms.展开更多
Advanced multifunctional composite phase change materials(PCMs)integrating dual-field excitative thermal storage and microwave absorption have been recently highlighted in cutting-edge applications.Herein,we designed ...Advanced multifunctional composite phase change materials(PCMs)integrating dual-field excitative thermal storage and microwave absorption have been recently highlighted in cutting-edge applications.Herein,we designed a metal–organic framework(MOF)derived magnetic NiCo-modified open carbon microcage(NiCo@C)for the encapsulation of PCMs,which simultaneously achieve fast-response multienergy capture and bimode stealth functions:The NiCo@C/PW composite PCMs exhibited a relatively high phase change enthalpy of 130.39 J/g due to the high cavity volume of the NiCo@C microcage.Strikingly,the composite PCMs demonstrated excellent solar-thermal conversion,attributed to the local surface plasmon resonance effect of NiCo nanoparticles and full-spectrum absorption of high graphitized carbon microcage.Simultaneously,composite PCMs harvested high-efficiency magnetic-thermal conversion due to the Néel and Brownian relaxation effects of diffusely embedded magnetic NiCo nanoparticles.More importantly,this thermal energy storage system achieved high-performance microwave absorption with a minimum reflection loss(RL)of−38.1 dB at 11.8 GHz at only 2.35 mm thickness.Our designed all-in-one strategy created an innovative platform for constructing advanced multifunctional microwave-absorbing composite PCMs with thermal storage,dual-energy conversion,microwave absorption,and infrared stealth.展开更多
基金support from the National Natural Science Foundation of China(21471039,21571043,21671047,and 21871065).
文摘Semiconductor materials with roughened surfaces offer great advantages for surface enhanced Raman spectroscopy(SERS)based on a chemical enhancement mechanism.Herein,M(OH)_(x)(M=Fe,Co,Ni)hollow octahedral microcages are synthesized and explored as novel SERS-active substrates for sensitive dye molecule detection.A single as-prepared hollow M(OH)x micro-octahedron particle with hierarchical surface architecture can be used as a highly sensitive SERS platform without interference from the surrounding environment.A comparative study indicates that Ni(OH)_(2) microcages can provide optimal Raman enhancement of various dye molecules with an enhancement factor of up to 2.35×10^(3),due to stronger coupling interactions between the dye molecule and metal center,which greatly facilitate the electron transfer process.This work can expand the availability of SERS substrates with higher sensitivity and stability,and focus more attention on an in-depth understanding of chemical enhancement mechanisms.
基金financially supported by the National Natural Science Foundation of China(NSFC,grant nos.52373261,52377026,and 51902025)Taishan Scholars and Young Experts Program of Shandong Province,China(grant no.tsqn202103057).
文摘Advanced multifunctional composite phase change materials(PCMs)integrating dual-field excitative thermal storage and microwave absorption have been recently highlighted in cutting-edge applications.Herein,we designed a metal–organic framework(MOF)derived magnetic NiCo-modified open carbon microcage(NiCo@C)for the encapsulation of PCMs,which simultaneously achieve fast-response multienergy capture and bimode stealth functions:The NiCo@C/PW composite PCMs exhibited a relatively high phase change enthalpy of 130.39 J/g due to the high cavity volume of the NiCo@C microcage.Strikingly,the composite PCMs demonstrated excellent solar-thermal conversion,attributed to the local surface plasmon resonance effect of NiCo nanoparticles and full-spectrum absorption of high graphitized carbon microcage.Simultaneously,composite PCMs harvested high-efficiency magnetic-thermal conversion due to the Néel and Brownian relaxation effects of diffusely embedded magnetic NiCo nanoparticles.More importantly,this thermal energy storage system achieved high-performance microwave absorption with a minimum reflection loss(RL)of−38.1 dB at 11.8 GHz at only 2.35 mm thickness.Our designed all-in-one strategy created an innovative platform for constructing advanced multifunctional microwave-absorbing composite PCMs with thermal storage,dual-energy conversion,microwave absorption,and infrared stealth.
