title: Construction of 3D V2O5/hydrogenated-WO3 nanotrees on tungsten foil for high-performance pseudocapacitors.
abstract: 3D semiconductor nanostructures have proved to be a rich system for the exploring of high-performance pseudocapacitors. Herein, a novel 3D WO3 nanotree on W foil is developed via a facile and green method. Both capacitance and conductivity of the WO3 nanotree electrode are greatly improved after hydrogenation treatment (denoted as H-WO3). First-principles calculation based on the experiments reveals the mechanism of the hydrogenation treatment effect on the 3D WO3 nanotrees. The surface O of 3D WO3 nanotrees gains electrons from the adsorbed H, and consequently certain electrons are back-donated to the neighboring W, thus providing the conducting channel on the surface. Ultrathin V2O5 films were coated on the H-WO3 nanotrees via a simple, low-cost, environmentally friendly electrochemical technique. This V2O5/H-WO3 electrode exhibited a remarkable specific capacitance of 1101 F g(-1) and an energy density of 98 W h kg(-1). The solid-state device based on the V2O5/H-WO3 electrodes shows excellent stability and practical application. Our work opens up the potential broad application of hydrogenation treatment of semiconductor nanostructures in pseudocapacitors and other energy storage devices.
authors.affiliation: National Center for Nanoscience and Technology, Beijing 100190, P. R. China. hej@nanoctr.cn.
authors.forename: Fengmei
authors.initials: F
authors.lastname: Wang
authors.forename: Yuanchang
authors.initials: Y
authors.lastname: Li
authors.forename: Zhongzhou
authors.initials: Z
authors.lastname: Cheng
authors.forename: Kai
authors.initials: K
authors.lastname: Xu
authors.forename: Xueying
authors.initials: X
authors.lastname: Zhan
authors.forename: Zhenxing
authors.initials: Z
authors.lastname: Wang
authors.forename: Jun
authors.initials: J
authors.lastname: He