二氧化锡(SnO_(2))具有高的理论比容量,有望作为下一代锂离子电池负极材料.然而,Sn向SnO_(2)的不可逆转化以及充放电过程中巨大的体积变化限制了其实际的应用.本文基于三维互连多孔氧化铝模板,设计合成了一种由内腔同时填充NiO和SnO_(2...二氧化锡(SnO_(2))具有高的理论比容量,有望作为下一代锂离子电池负极材料.然而,Sn向SnO_(2)的不可逆转化以及充放电过程中巨大的体积变化限制了其实际的应用.本文基于三维互连多孔氧化铝模板,设计合成了一种由内腔同时填充NiO和SnO_(2)纳米颗粒的碳管基元相互连接组成的三维碳管网格膜,可以直接作为自支撑的高性能锂离子电池负极.该复合框架利用了NiO和SnO_(2)纳米颗粒的协同作用,不仅能够促进Sn向SnO_(2)的可逆转变,提高首次库伦效率,而且还可以缓释充放电过程中SnO_(2)剧烈的体积变化.此外,相互连接的三维碳管框架可以负载大量NiO和SnO_(2)纳米颗粒,缩短Li+的扩散距离,并作为快速的电子传输通道.因此,这种独特的结构赋予了该电极超高的储锂容量和倍率性能在1 A g^(-1)循环200次后,比容量达到928.5 mA h g^(-1),并且在4 A g^(-1)的高电流密度下仍然具有633.5 mA h g^(-1)的比容量.总之,这种独特的一体化结构在锂离子电池等储能领域具有广阔的应用前景.展开更多
The straight channel optical waveguide coated with the SnO_(2) nanoparticle is studied as an all-optical humidity sensor.The proposed sensor shows that the transmission loss of the waveguide increases with increasing ...The straight channel optical waveguide coated with the SnO_(2) nanoparticle is studied as an all-optical humidity sensor.The proposed sensor shows that the transmission loss of the waveguide increases with increasing relative humidity(RH)from 56%to 90%with very good repeatability.The sensitivity to changes in relative humidity is~2 dB/%RH.The response time of the humidity sensor is 2.5 s,and the recovery time is 3.5 s.The response to humidity can be divided into 3 different regions,which are correlated to the degree of water adsorption in the SnO_(2) nanoparticle layer.Compared with the previous all-optical humidity sensor based on SnO_(2),the proposed sensor exhibits more rapid response,simpler fabrication process,and higher sensitivity.The proposed sensor has a potential application in the long distance,remote agriculture,and biological humidity sensing.展开更多
基金supported by the National Natural Science Foundation of China (91963202 and 52072372)the Key Research Program of Frontier Sciences (CAS, QYZDJ-SSW-SLH046)+1 种基金the CAS/SAFEA International Partnership Program for Creative Research TeamsHefei Institutes of Physical Science, Chinese Academy of Sciences Director’s Fund (YZJJZX202018)。
文摘二氧化锡(SnO_(2))具有高的理论比容量,有望作为下一代锂离子电池负极材料.然而,Sn向SnO_(2)的不可逆转化以及充放电过程中巨大的体积变化限制了其实际的应用.本文基于三维互连多孔氧化铝模板,设计合成了一种由内腔同时填充NiO和SnO_(2)纳米颗粒的碳管基元相互连接组成的三维碳管网格膜,可以直接作为自支撑的高性能锂离子电池负极.该复合框架利用了NiO和SnO_(2)纳米颗粒的协同作用,不仅能够促进Sn向SnO_(2)的可逆转变,提高首次库伦效率,而且还可以缓释充放电过程中SnO_(2)剧烈的体积变化.此外,相互连接的三维碳管框架可以负载大量NiO和SnO_(2)纳米颗粒,缩短Li+的扩散距离,并作为快速的电子传输通道.因此,这种独特的结构赋予了该电极超高的储锂容量和倍率性能在1 A g^(-1)循环200次后,比容量达到928.5 mA h g^(-1),并且在4 A g^(-1)的高电流密度下仍然具有633.5 mA h g^(-1)的比容量.总之,这种独特的一体化结构在锂离子电池等储能领域具有广阔的应用前景.
基金supported by the Ministry of Research,Technology&Higher Education of Indonesia with PMDSU scholarship fundingthe Malaysia Ministry of Higher Education(MOHE)(LRGS(2015)/NGOD/UM/KPT)。
文摘The straight channel optical waveguide coated with the SnO_(2) nanoparticle is studied as an all-optical humidity sensor.The proposed sensor shows that the transmission loss of the waveguide increases with increasing relative humidity(RH)from 56%to 90%with very good repeatability.The sensitivity to changes in relative humidity is~2 dB/%RH.The response time of the humidity sensor is 2.5 s,and the recovery time is 3.5 s.The response to humidity can be divided into 3 different regions,which are correlated to the degree of water adsorption in the SnO_(2) nanoparticle layer.Compared with the previous all-optical humidity sensor based on SnO_(2),the proposed sensor exhibits more rapid response,simpler fabrication process,and higher sensitivity.The proposed sensor has a potential application in the long distance,remote agriculture,and biological humidity sensing.
