title: Self-Assembly of Parallelly Aligned NiO Hierarchical Nanostructures with Ultrathin Nanosheet Subunits for Electrochemical Supercapacitor Applications.
abstract: Parallelly aligned NiO hierarchical nanostructures were fabricated using a templated self-assembly method followed by calcinations, where rationally employed pluronic triblock copolymers (P123) are acting as molecular templates for geometrical manipulation of nanocrystals and short-chain alcohols are acting as cosolvents and cosurfactants. Such aligned nanostructure is constructed orderly with several ultrathin two-dimensional (2D) nanosheet subunits with an exceptionally small thickness of only 3 nm in a high degree of orientation and separation. Moreover, the number of assembled nanosheets in a unit can be tuned by changing the concentration of the involving P123. This is the first time to synthesize highly hierarchically ordered and bilaterally symmetrical nanostructures, distributed in diameter of around 200-300 nm, via self-assembly in the liquid phase without solid substrates. The as-synthesized NiO delivered high capacitances of 418 F/g at the current density of 2 A/g with well cycling stability (still maintained 85% after 2000 cycles) and 333 F/g at 10 A/g in rates performance after 60 cycles. These fine electrochemical performances are supposed to be attributed to the hierarchical structures with high specific surface area (SSA, ∼164.87 m(2)/g) and ordered multilevel mesopores, which facilitate the electrolyte accessibility and provide more active sites for redox reaction.
authors.affiliation: School of Materials Science and Engineering, Central South University , Changsha 410083, Hunan China.
authors.forename: Jie
authors.initials: J
authors.lastname: Min
authors.affiliation: School of Materials Science and Engineering, Central South University , Changsha 410083, Hunan China.
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications , Beijing 100876, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Lei
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Wenjun
authors.initials: W
authors.lastname: Wang
authors.affiliation: School of Materials Science and Engineering, Central South University , Changsha 410083, Hunan China.
authors.forename: Yakun
authors.initials: Y
authors.lastname: Lu
authors.affiliation: School of Materials Science and Engineering, Central South University , Changsha 410083, Hunan China.
authors.forename: Linyu
authors.initials: L
authors.lastname: Yang
authors.affiliation: School of Materials Science and Engineering, Central South University , Changsha 410083, Hunan China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Department of Hepatobiliary Pancreas Surgery, Xiangya Hospital , Changsha, Hunan 410008, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Liu
authors.affiliation: School of Materials Science and Engineering, Central South University , Changsha 410083, Hunan China.
authors.forename: Nan
authors.initials: N
authors.lastname: Su
keywords: P123-assisted self-assembly; high-rate performance; layers controllable; multilevel mesopores; parallelly aligned NiO hierarchical nanostructures; supercapacitor; ultrathin nanosheet subunits