Porous Ultrathin NiSe Nanosheet Networks on Nickel Foam for High‐Performance Hybrid Supercapacitors

Abstract

Transition metal selenides (TMSs) with excellent electrochemical activity and high intrinsic electrical conductivity have attracted considerable attention owing to their potential use in energy storage devices. However, the low energy densities of the reported TMSs, which originate from the small active surface area and poor electrolyte ion mobility, substantially restrict their application potential. In this work, porous ultrathin nickel selenide nanosheet networks (NiSe NNs) on nickel foam are fabricated by using a novel, facile method, that is, selenylation/pickling of the pre‐formed manganese‐doped α‐Ni(OH)2. Removal of Mn resulted in NNs with a highly porous structure. The 3D framework of the NNs and the inherent nature of the NiSe affords high ion mobility, abundant accessible activated sites, vigorous electrochemical activity, and low resistance. One of the highest specific capacities of TMSs ever reported, that is, 443 mA h g−1 (807 μAh cm−2) at 3.0 A g−1, is achieved with the NNs as electrodes. The assembled NiSe NNs//porous carbon hybrid supercapacitor delivers a high energy density of 66.6 Wh kg−1 at a power density of 425 W kg−1, with excellent cycling stability. This work provides a new strategy for the production of novel electrode materials that can be applied in high‐performance hybrid supercapacitors, and a fresh pathway towards commercial applications of hybrid supercapacitors based on TMS electrodes.

Boron-Doped Trimetallic Cu-Ni-Co Oxide Nanoneedles for Supercapacitor Application

“…15 However, till date, flawless HSCs have not been reported for large-scale application. Metal oxides (NiO), 16 T h i s c o n t e n t i s hydroxides (Co (OH) 2 ), 17 sulfides (NiS), 18 and selenides (NiSe) 19 have been investigated as HSCs. However, due to a limited number of redox reactions, they exhibit poorer electrochemical performance than bimetallic compounds.…”

Asymmetric polyhedron structured NiSe2@MoSe2 device for use as a supercapacitor

“…Recently, the transition metal selenides have been regarded as the promising candidate with good conductivity and electrochemical activity [13]. Particularly, metal selenide shows superior electrochemical properties in consequence of material architecture enhancing the large surface area which provides and accelerates redox reaction [14].…”

In SituPhase Transformation on Nickel-Based Selenides for Enhanced Hydrogen Evolution Reaction in Alkaline Medium

“…When the crystal further transforms into hexagonal NiSe, the Ni d-band also passes through the Fermi level with increased energy in states, which is in accordance with previous literature contributions. 39,40 The d-band center and occupied electron numbers in Ni d-band and Se p-band are also calculated as shown in Table S5. The d-band center 41 is a reasonable descriptor to predict the catalytic activity of transition metals, which is a measure of the strength between metal and absorbate (i.e., hydrogen adsorption energy).…”