【摘 要】
：
Boron nitride (BN) aerogels,composed of nanoscale BN building units together with plenty of air in between these nanoscale building units,are ultralight ceramic materials with excellent thermal/electrical insulation,great chemical stability and high-tempe
【机 构】
：
School of Nano-Tech and Nano-Bionics,University of Science and Technology of China,Hefei 230026,Peop
论文部分内容阅读
Boron nitride (BN) aerogels,composed of nanoscale BN building units together with plenty of air in between these nanoscale building units,are ultralight ceramic materials with excellent thermal/electrical insulation,great chemical stability and high-temperature oxidation resistance,which offer considerable advantages for various applications under extreme conditions.However,previous BN aerogels cannot resist high temperature above 900 ℃ in air atmosphere,and high-temperature oxidation resistance enhancement for BN aerogels is still a great challenge.Herein,a calcium-doped BN (Ca-BN) aerogel with enhanced high-temperature stability (up to ～ 1300 ℃ in air) was syn-thesized by introducing Ca atoms into crystal structure of BN building blocks via high-temperature reaction between calcium phosphate and melamine diborate architecture.Such Ca-BN aerogels could resist the burning of butane flame (～ 1300 ℃) and keep their megashape and microstructure very well.Furthermore,Ca-BN aerogel serves as thermal insulation layer,together with A1 foil serving as both low-infrared-emission layer and high-infrared-reflection layer,forming a combination structure that can effectively hide high-temperature target (heated by butane flame).Such successful chemical doping of metal element into crystal structure of BN may be helpful in the future design and fabrication of advanced BN aerogel materials,and further extending their possible applications to extremely high-temperature environments.
其他文献
The application of ionic liquids in perovskite has attracted wide-spread attention for its astounding performance improvement of perovskite solar cells (PSCs).However,the detailed mechanisms behind the improvement remain mysterious.Herein,a series of imid
Due to their high safety and low cost,rechargeable aqueous Zn-ion batteries (RAZIBs) have been receiving increased attention and are expected to be the next generation of energy storage systems.However,metal Zn anodes exhibit a limited-service life and in
Real-time rapid detection of toxic gases at room temperature is particularly important for public health and environmental monitoring.Gas sensors based on conventional bulk materials often suffer from their poor surface-sensitive sites,leading to a very l
Iron hexacyanoferrate (FeHCF) is a promising cathode material for sodium-ion batteries.However,FeHCF always suffers from a poor cycling stability,which is closely related to the abundant vacancy defects in its framework.Herein,post-synthetic and in-situ v
Here,this work presents an air-stable ultrabright inverted organic light-emitting device (OLED) by using zinc ion-chelated polyethylenimine (PEI) as electron injection layer.The zinc chelation is dem-onstrated to increase the conductivity of the PEI by th
Solar steam generation technology has emerged as a promising approach for seawater desalination,wastewater purification,etc.However,simultaneously achieving superior light absorption,ther-mal management,and salt harvesting in an evaporator remains challen
Although advances in wireless technologies such as miniature and wearable electronics have improved the quality of our lives,the ubiquitous use of electronics comes at the expense of increased exposure to electromagnetic (EM)radiation.Up to date,extensive
The processing capability is vital for the wide appli-cations of materials to forge structures as-demand.Graphene-based macroscopic materials have shown excellent mechanical and func-tional properties.However,different from usual polymers and met-als,grap
The recombination loss of photo-carriers in photocatalytic systems fatally determines the energy conversion efficiency of photocata-lysts.In this work,an electrostatic field was used to inhibit the recom-bination of photo-carriers in photocatalysts by sep
Two-dimensional (2D) MXenes are promising as electrode materials for energy storage,owing to their high electronic conductivity and low diffusion bar-rier.Unfortunately,similar to most 2D materials,MXene nanosheets easily restack during the electrode prep