锂硒电池因其可观的体积比容量(3254 m A·h/cm3),已经引起了国内外研究学者们的广泛关注。本文在介绍锂硒电池硒/碳正极材料的基础上,指出了锂硒电池目前存在的主要问题,并提出了可能的解决方案,最后对未来锂硒电池的研究方向做出...锂硒电池因其可观的体积比容量(3254 m A·h/cm3),已经引起了国内外研究学者们的广泛关注。本文在介绍锂硒电池硒/碳正极材料的基础上,指出了锂硒电池目前存在的主要问题,并提出了可能的解决方案,最后对未来锂硒电池的研究方向做出了展望。展开更多
Flexible supercapacitors (SCs) are attractive energy storage devices for wearable electronics, but their applications are hindered by their low volumetric energy densities. Two dimensional (2D) non-carbon nanomaterial...Flexible supercapacitors (SCs) are attractive energy storage devices for wearable electronics, but their applications are hindered by their low volumetric energy densities. Two dimensional (2D) non-carbon nanomaterials are the most promising pseudocapacitive materials for high volumetric capacitance electrodes. However, they are poorly conductive and prone to self-stacking, which results in unsatisfactory electrochemical performance. In this work, large-scale V2O5·nH2O ultrathin nanosheets are synthesized by a facile and scalable method and transformed into layered and compact composite films with one-dimensional carbon nanotubes (CNTs). The self-standing films show an optimized volumetric capacitance of 521.0Fcm^-3 with only 10 wt% of CNTs, which is attributed to dramatically enhanced electrical conductivity beyond the electrical percolation threshold, high dispersion of pseudocapacitive V2O5·nH2O nanosheets, and high mass density of the films. All-solid-state flexible SCs made of V2O5·nH2O/CNTs films show a maximum energy density of 17.4WhL^-1.展开更多
基金supported by the National Natural Science Foundation of China (51702048 and 21603157)the National Basic Research Program of China (2015CB932600)Jiangxi Provincial Department of Education (GJJ170459 and GJJ170457)
文摘Flexible supercapacitors (SCs) are attractive energy storage devices for wearable electronics, but their applications are hindered by their low volumetric energy densities. Two dimensional (2D) non-carbon nanomaterials are the most promising pseudocapacitive materials for high volumetric capacitance electrodes. However, they are poorly conductive and prone to self-stacking, which results in unsatisfactory electrochemical performance. In this work, large-scale V2O5·nH2O ultrathin nanosheets are synthesized by a facile and scalable method and transformed into layered and compact composite films with one-dimensional carbon nanotubes (CNTs). The self-standing films show an optimized volumetric capacitance of 521.0Fcm^-3 with only 10 wt% of CNTs, which is attributed to dramatically enhanced electrical conductivity beyond the electrical percolation threshold, high dispersion of pseudocapacitive V2O5·nH2O nanosheets, and high mass density of the films. All-solid-state flexible SCs made of V2O5·nH2O/CNTs films show a maximum energy density of 17.4WhL^-1.
