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.

Ni@NiO core/shell dendrites for ultra-long cycle life electrochemical energy storage

“…1 Nickel based materials have been identied as promising electrode materials for electrochemical energy storage devices because of their high theoretical specic capacitance ($2584 F g À1 for NiO and 2082 F g À1 for Ni(OH) 2 ), environmental friendliness and low cost. 2,3 With the aim to provide a larger reaction area and shorten ion diffusion paths, many fabrication methods including chemical precipitation, 4,5 hydrothermal synthesis, [6][7][8][9][10][11] sol-gel, 12,13 thermal oxidation [14][15][16] and anodization 17,18 have been used to produce various kinds of nickel-based nanostructures, such as amorphous Ni(OH) 2 nanoboxes, 5 Ni-Co oxide nanowires, 6,19 Ni(OH) 2 nanosheets, 7,11 NiO nanobelts, 8 nanosized rambutan-like NiO, 9 urchin-like NiCo 2 O 4 , 10 spinel nickel cobaltite aerogels, 12 NiO nanoowers, 13 NiO nanoblocks 14 and sponge-like Ni(OH) 2 -NiF 2 composites. 18 Apart from the above methods, electrodeposition has gained more and more attention because the electroactive material can be directly grown on a current collector without the need for using any binder or conducting agent.…”

Ultra high supercapacitance of ultra small Co3O4 nanocubes

“…These plots demonstrate that nearly 80% of specific capacitance and Coulombic efficiency retain upon increasing current density from 8 to 100 A g À1 . Furthermore, the energy (E) and the specific power (P) densities of the electrodes were calculated by using the equations [10],…”

“…The electrode material is one of the most crucial components that governs the overall electrochemical performance of the SCs. In order to improve SCs' energy density, numerous efforts have been directed to investigate pseudocapacitive transition metal oxides or hydroxides (such as RuO 2 [4], MnO 2 [5], Mn 3 O 4 [6], NiO [7,8], Co 3 O 4 [9], Ni(OH) 2 [10], Co(OH) 2 [11], NiCo 2 O 4 [12,13] etc. ), and coreeshell structures of metal/metal oxides/metal sulfides [14,15] which have potential to produce higher specific capacitance, in comparison with typical carbonaceous materials used in EDLC.…”

Amorphous Ni–P materials for high performance pseudocapacitors

“…However, the high cost and toxic nature restrict its commercial application [15,16]. In contrast, transition metal oxides, such as NiO x [17,18], MnO 2 [19e21], and V 2 O 5 [22,23], show the advantages of low cost, environmental safety, high theoretical specific capacitance, and also have been applied extensively in pseudocapacitors. Unfortunately, one of the main conclusions about these materials is the poor electronic conductivity compared with RuO 2 , which severely limits the practical capability of such oxides based electrodes, especially at a fast scan rate or a high current density during the chargeedischarge process.…”