Short CommunicationHierarchical copper selenide nanoneedles grown on copper foil as a binder free electrode for supercapacitors
Introduction
Supercapacitors or electrochemical capacitors have attained much interest among the various energy storage devices due to their high power density with long cycle life [1]. Supercapacitors become a bridge between batteries and capacitors via storing a large amount of charge, and deliver it at a high power rating. Supercapacitors are widely classified into two categories viz. (i) electrical double layer capacitors (EDLCs) and (ii) pseudocapacitors based upon their charge storage mechanism [2]. The mechanism of charge storage in EDLCs relies on the accumulation of electrostatic charge at the electrode/electrolyte interface whereas pseudocapacitance arises due to reversible Faradaic reactions occurred at the electrode surface. In this decade, researchers focused on utilizing two dimensional transition metal chalcogenides (TMCs) as alternative electrodes for supercapacitors. The supercapacitive properties and mechanism of charge storage in TMCs such as MoS2, Ni3S4, CoS, WS2, and CuS nanostructures are widely investigated until now [3], [4]. On the other hand, the use of TMCs such as metal selenides and tellurides towards electrochemical energy storage are not extensively studied compared to that of metal sulfides. The development of novel electrode with more energy and power density for supercapacitor applications is an emerging area of interest during the recent decade. In this scenario, transition metal selenides are more promising than transition metal oxides [5], [6] for using as an electrode material for supercapacitors owing to their high electronic conductivity and multiple oxidation states. Very recently, few studies reported the use of metal selenides such as CoSe, and SnSe for supercapacitors [7], [8]. Hitherto, there are no reports available in the literature regarding the electrochemical properties of copper selenide nanostructures. It is well known that copper-based oxides, binary metal oxides, and sulfides showed better electrochemical properties [9]. Copper selenide is a low cost semiconducting material having applications in the field of optoelectronics, thermoelectrics, and solar cells [10], [11]. The advantage of copper selenide is its various oxidation states and high electrical conductivity compared with metal oxides, which can deliver better electrochemical properties. In this study, we demonstrate the preparation of hierarchical nanostructured copper selenide grown on copper foil via hydrothermal reaction and investigated their electrochemical properties for potential use as a binder-free electrode for supercapacitor applications.
Section snippets
Materials used
Sodium selenite was purchased from Alfa Aesar, South Korea. Copper (Cu) foil was purchased from Nilaco, Japan. All chemicals used in this work are of research grade and used without further purification.
Growth of CuSe2 on Cu foil
A one pot hydrothermal method was employed for the growth of CuSe2 on Cu foil. The Cu foil acts as both substrate as well as Cu source and sodium selenite acts as Se source. Briefly, the Cu foil (3 × 4 cm) was cleaned with acetone, ethanol and then dried at 60 °C. An aqueous solution of 1 M
Results and discussion
Fig. 1(a) shows the digital photograph of the Cu foil before and after the hydrothermal reaction. It revealed that the color of the Cu foil changes from red-orange to dark black, thus confirming the formation of copper selenide on either side of Cu foil. In general, copper selenide can occur in different phases and compositions such as CuSe, Cu2Se, CuSe2, Cu3Se2, respectively [11]. The X-ray diffraction pattern of the final product (shown in Fig. 1(b)) revealed the presence of major diffraction
Conclusions
The key findings of this work suggested the use of CuSe2 nanoneedles grown on Cu foil as a binder-free electrode for high performance supercapacitors. The CV profiles and EIS analyses (Nyquist and Bode plots) confirmed the pseudocapacitive nature of the CuSe2/Cu electrode. Galvanostatic charge–discharge analysis revealed that the CuSe2/Cu binder-free electrode delivered a high specific capacitance of about 1037.5 F/g with a corresponding energy density of 51.85 Wh/kg and power density of
Acknowledgments
This work was supported by the National Research Foundation of Korea (NRF) funded by the Korea Government GRANT (2016R1A2B2013831) and by the Jeju Sea Grant College Program 2016 Funded by the Ministry of Oceans and Fisheries (MOF), Korea.
References (24)
- et al.
Preparation of electrospun Co3O4 nanofibers as electrode material for high performance asymmetric supercapacitors
Electrochim Acta
(2014) - et al.
Effect of reducing agent on graphene synthesis and its influence on charge storage towards supercapacitor applications
Appl Energy
(2015) - et al.
Designing two dimensional nanoarchitectured MoS2 sheets grown on Mo foil as a binder free electrode for supercapacitors
Electrochim Acta
(2016) - et al.
Synthesis of reduced graphene oxide wrapped-copper sulfide hollow spheres as electrode material for supercapacitor
Int J Hydrogen Energy
(2015) - et al.
Three-dimensional Ni(OH)2 nanoflakes/graphene/nickel foam electrode with high rate capability for supercapacitor applications
Int J Hydrogen Energy
(2014) - et al.
Flexible solid-state CuxO-based pseudo-supercapacitor by thermal oxidation of copper foils
Int J Hydrogen Energy
(2016) - et al.
A novel aqueous asymmetric supercapacitor based on petal-like cobalt selenide nanosheets and nitrogen-doped porous carbon networks electrodes
J Power Sources
(2015) - et al.
Thermoelectric properties of copper selenide with ordered selenium layer and disordered copper layer
Nano Energy
(2012) - et al.
Template free-solvothermaly synthesized copper selenide (CuSe, Cu2−xSe, β-Cu2Se and Cu2Se) hexagonal nanoplates from different precursors at low temperature
J Cryst Growth
(2010) - et al.
Fabrication of porous Ni3S2/Ni nanostructured electrode and its application in lithium ion battery
Mater Chem Phys
(2012)
Cited by (90)
Advanced 3D hierarchical composite electrode materials for supercapacitors: Biomass derived carbon doped CoMoO<inf>4</inf>@NiCo<inf>2</inf>O<inf>4</inf>
2024, Colloids and Surfaces A: Physicochemical and Engineering AspectsCoSe<inf>2</inf>@ZnS microsphere arrays with remarkable electrochemical performance for hybrid asymmetric supercapacitor
2023, Journal of Energy StorageNanoarchitectonics of self-grown copper selenide on copper for solid-state asymmetric supercapacitor
2023, Journal of Energy Storage