title: Hydrogenated NiO nanoblock architecture for high performance pseudocapacitor.
abstract: Supercapacitor electrodes are fabricated with the self-organized 3D architecture of NiO and hydrogenated NiO (H-NiO) nano-blocks (NBs) grown by the facile electrodeposition and high temperature annealing of the Ni foil on Cu substrate. The unique architecture of H-NiO NBs electrode exhibits excellent cycling stability (only 5.3% loss of its initial specific capacitance after 3000 cycles at current density of 1.1 A g(-1)) along with the high specific and areal capacitance of ∼1272 F g(-1) and 371.8 mF cm(-2), respectively at scan rate of 5 mV s(-1) compared with the pure NiO NBs electrode (∼ 865 F g(-1) and 208.2 mF cm(-2), respectively at scan rate of 5 mV s(-1)). H-NiO NBs electrode also exhibits excellent rate capability; nearly 61% specific capacity retention has been observed when the current density increases from 1.11 to 111.11 A g(-1). This electrode offers excellent energy density of 13.51 Wh kg(-1) and power density of 19.44 kW kg(-1) even at a high current density of 111.11 A g(-1). The superior pseudocapacitive performance of the H-NiO NBs electrode is because of the high electron and ion conductivity of the active material because of the incorporation of hydroxyl groups on the surface of NiO NBs.
authors.affiliation: Department of Condensed Matter Physics and Material Sciences, S. N. Bose National Centre for Basic Sciences , Block JD, Sector III, Salt Lake City, Kolkata 700 098, India.
authors.forename: Ashutosh K
authors.initials: AK
authors.lastname: Singh
authors.forename: Debasish
authors.initials: D
authors.lastname: Sarkar
authors.forename: Gobinda Gopal
authors.initials: GG
authors.lastname: Khan
authors.forename: Kalyan
authors.initials: K
authors.lastname: Mandal