Copper Cobalt Sulfide Research Articles

The performance and mechanism of copper-cobalt sulfide cathode for hybrid Mg2+/Li+ batteries

Hybrid Mg2+/Li+ batteries are a potential energy storage device possessing fast ion migration kinetics and high safety. As a ternary transition metal sulfide, the CuCo2S4 with high theoretical capacity is an ideal conversion-type cathode material and it has been successfully synthesized via one step solvothermal method in this work. At room temperature, combined with hybrid Mg2+/Li+ batteries electrolyte prepared by adding LiCl salts to all-phenyl complex (APC) electrolyte (LiCl-APC hybrid electrolyte) as well as Mg metal anode, the CuCo2S4 cathode demonstrates a high discharge capacity of 517.5 mA h g−1 at the current density of 0.1 C. And it shows good long-term cycle performance with the reversible capacities of 172.3 mA h g−1 and 86.6 mA h g−1 even over 100 cycles at 0.1 C and 0.5 C, respectively. In addition, the reaction mechanism is revealed by ex-situ X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) characterizations. The results show that CuCo2S4 is converted to new active materials (CuS, CoS and Co9S8) after the first cycle, and then completely changes into CuS and CoS after 10 cycles due to the transformation of Co9S8 into CoS during the cycling. As a result, CoS and CuS dominate the subsequent reversible cycles. This work confirms that CuCo2S4 is an appropriate cathode material for high performance hybrid Mg2+/Li+ batteries.

The Metallogeny of the Lubei Ni–Cu–Co Sulfide Deposit in Eastern Tianshan, NW China: Insights From Petrology and Sr–Nd–Hf Isotopes

The Lubei Ni–Cu–Co deposit situated in western segment of the Huangshan-Jing’erquan mafic–ultramafic rock belt in eastern Tianshan of the Central Asian Orogenic Belt (CAOB). The estimated reserve is approximately 9.11 million tons of ore resources with average grades of 0.82 wt% Ni, 0.52 wt% Cu, and 0.03 wt% Co. The Lubei intrusion is mainly composed of gabbro (phase I), peridotite (phase II), pyroxene peridotite (phase III), olivine pyroxenite (phase IV), and diorite (phase V), which intruded into the early Carboniferous tuffaceous clastic rocks. Zircon Laser Ablation–Inductively Coupled Plasma–Mass Spectrometry (LA–ICP–MS) U–Pb age of the diorite (phase V) from the edge of the intrusion is interpreted as the top-limit metallogenic age, which is consistent with the formation ages of the Huangshan and Xiangshan Ni–Cu deposits in eastern Tianshan. The roughly parallel rare earth element (REE) curves of the Lubei intrusion indicate the magma originated from a homologous source. The slightly enriched large ion lithophile elements (LILE) are compared to high field strength elements (HFSE) with negative Nb and Ta anomalies show that the Lubei intrusion has arc-affiliate geochemical characteristics. The Sr–Nd–Hf isotopes show that the magma was derived from depleted lithospheric mantle, while suffering 4–10% lower crustal contamination with slight contamination of the upper crust. Based on a comprehensive conservation of regional geological, geochemical, and geochronological evidence, the primary magma of the Lubei intrusion was identified that it was derived from the partial melting of metasomatized lithospheric mantle previously modified by subduction events. The Lubei nickel–copper–cobalt sulfide deposit was formed after the primary magma experienced fractional crystallization, crustal contamination, and sulfide segregation in a post-collisional extensional geodynamic setting after the closure of the Kanggur ocean basin in the early Permian.

3D hollow cage copper cobalt sulfide derived from metal–organic frameworks for high-performance asymmetric supercapacitors

The fabrication of the advanced MOF-based 3D hollow cage ternary bimetallic material CuCo2S4 for high performance asymmetric supercapacitors.

Highly efficient copper-cobalt sulfide nano-reeds array with simplistic fabrication strategy for battery-type supercapacitors

Selected material combination, higher electrical conductivity, and high specific capacity were cognizance to favor supercapacitors (SCs), but their recognition at the same time has still a great challenger task. Herein, we demonstrate on copper-cobalt sulfide nano-reeds array with excellent nanoarchitecture has been developed by simplistic hydrothermal approach for SCs. The as-developed Cu-Co sulfide nano-reeds array possesses boosted electrochemical activities. In the performed SCs results, a specific capacity of 158.93 mA h g−1 has been reported at a current density of 2 A g−1 with well capability rate of 86.6% of the first capacity was remain at 20 A g−1. The effects of highly electroactive capabilities of Cu-Co sulfide nano reeds array electrode was optimized so that 93.1% of the first capacitance has been exhibited after 4000 cycles at 5 A g−1. Finally, these better most results demonstrated that the Cu-Co sulfide nano-reeds array material presents a progressive electroactive material for the future generation energy storage applications.

Construction of complex copper-cobalt selenide hollow structures as an attractive battery-type electrode material for hybrid supercapacitors

The application of battery-like electrode materials with complex hollow structures, huge surface areas, and good redox properties is an appealing approach towards the boosting performance of hybrid supercapacitors. This work proposes a facile strategy for the fabrication of copper-cobalt selenide hollow spheres (CCSe-HSs) as a new battery-type electrode for hybrid supercapacitors. Benefiting from the considerable electrical conductivity and rationally porous structures, this electrode exhibits a higher capacitance/capacity of 1775.4F g−1/295.9 mAh g−1 compared with copper-cobalt sulfide hollow spheres (CCS-HSs) and copper-cobalt oxide hollow spheres (CCO-HSs). Besides, an advanced device (CCSe-HSs//AC) constructs by combining copper-cobalt selenide hollow spheres (positive electrode) and activated carbon (AC, negative electrode). Our device reflects reasonable energy and power densities (53.86 W h kg−1 at 800 W kg−1, respectively), and desirable cyclability. Our current study provides a rationale and efficient design strategy to engineer new bimetallic selenides with complex hollow structures for different applications.

Rational design of copper-cobalt sulfide anchored on Ni-foam as high-performance supercapacitor electrode

Binder-free electrode of CuCo2S4 composite with three-dimensional (3D) porous structure grown directly on Ni foam is obtained by a facile one-step hydrothermal method. The optimal CuCo2S4/NF material shows unique cross-networked hierarchical structure and excellent electrochemical performance, with a high specific capacitance (3252 F g−1 at 1 A g−1) and a superior cycling performance (91.8% after 2000 charge/discharge cycles at 8 A g−1). The superior electrochemical performance is related to the binder-free 3D heterostructure of the open geometry, which provides enrichment of pored-structure and an excellent channel for a more sustainable and efficient energy storage and conversion.

High-performance asymmetric supercapacitors realized by copper cobalt sulfide crumpled nanoflower and N, F co-doped hierarchical nanoporous carbon polyhedron

Supercapacitors trigger tremendous interests in energy storage and conversion as they can safely provide high power density with long cycle life. However, the energy density of current supercapacitors is still restrained by microstructures and sluggish kinetics of electrode materials. Recently, zeolitic imidazolate frameworks (ZIFs) with excellent structural flexibility are demonstrated as one of promising precursors and templates to design novel supercapacitor electrode materials with high specific area and rich redox active sites. This work presents a systematic study of synthesis and characterizations of single ZIF-67-derived mesoporous copper cobalt sulfide (CuCo2S4) crumpled nanoflower and N, F co-doped hierarchical nanoporous carbon polyhedron (NFHPC). The obtained CuCo2S4 and NFHPC show superior capacitive performance due to abundant Faradic-redox active sites, efficient charge transport and excellent interfacial wettability. We further assemble an asymmetric supercapacitor based on CuCo2S4 as positive electrode and NFHPC as negative electrode. As a result, the assembled asymmetric supercapacitor achieves a high energy density of 55.1 Wh kg−1 at a power density of 799.8 W kg−1, and a long cycle life (91.1% of the initial capacitance after 5000 cycles). Our work thus provides an easy strategy to design effective electrode materials with superior performance for energy storage.

Effect of fluorine doping and sulfur vacancies of CuCo2S4 on its electrochemical performance in supercapacitors

The intriguing features of copper cobalt sulfide (CuCo2S4), such as multiple Faradaic reactions and abundant valance states, enable it a promising electrode material for supercapacitors. However, the sluggish transfer kinetics of charges and the insufficient number of active sites hamper its practical application. Herein, an efficient strategy was proposed to boost the electrochemical performance of CuCo2S4 through a synergetic incorporation of F dopants and S vacancies. The induced effects of F dopant and S vacancy of CuCo2S4 (denoted as F-CuCo2S4−x) on the physical characteristics and the electrochemical behaviors were investigated systemically. Experimental results reveal that through introduction of F dopants and S vacancies in dominant lattice, the low oxidation state concentrations of Cu and Co species are boosted remarkably, which lead to the improved electric conductivity and the enhanced interfacial activities of F-CuCo2S4−x, and facilitate the reaction kinetics. The as-synthesized F-CuCo2S4−x exhibits the ultrahigh specific capacity of 2202.7 C g−1 at 1 A g−1, and the excellent capacity retention of 96.7% after 5000 cycles at 20 A g−1. An asymmetric supercapacitor assembled with F-CuCo2S4−x and activated carbon as the positive and the negative electrodes, respectively, delivers the favorable energy density of 49.8 W h kg−1 at 897.39 W kg−1, as well as the long-term cycling lifetime. This study offers an effective strategy to optimize the transition metal compounds for electrochemical energy-storage devices.

Space-Confined Synthesis of Lasagna-like N-Doped Graphene-Wrapped Copper–Cobalt Sulfides as Efficient and Durable Electrocatalysts for Oxygen Reduction and Oxygen Evolution Reactions

Searching for efficient and economical bifunctional oxygen electrocatalysts is urgent for exploring sustainable energy technologies. Herein, the unique lasagna-like structured copper–cobalt sulfide...

Ternary CuCo2S4 Thiospinel Nanocrystal-Coated Photodiode with Improved Photoresponsivity and Acceptance Angles for Optoelectronic Applications

Ternary-structured thiospinels have attracted great attention in recent years for energy applications due to their attractive characteristics such as simple production, earth-abundant components and non-toxic nature. In this work, copper cobalt sulfide (CuCo2S4 or carrollite) thiospinel nanocrystals were synthesized by a hot-injection method, and detailed electrical and optoelectronic characterizations were performed in a Schottky device. The synthesized nanocrystals were used as an interfacial layer between the Au metal and p-Si semiconductor to obtain an Au/CuCo2S4/p-Si device. The structural and morphological characterizations confirmed the crystallinity, nanostructure and composition of the CuCo2S4 nanocrystals. The I–V and C–V measurements were employed to characterize the Au/CuCo2S4/p-Si device for various illumination intensities. The obtained device exhibited good rectifying and photodiode properties as well as good photocapacitance. The Au/CuCo2S4/p-Si device can be used and improved for optoelectronic applications.

Development of Copper Cobalt Sulfide with Cu : Co Ratio Variation on Carbon Cloth as an Efficient Electrode Material for the Oxygen Evolution Reaction

AbstractWhen designing a device for energy conversion, development of a highly active catalyst for OER (oxygen evolution reaction) reaction in alkaline medium is of utmost importance. For energy conversion, herein, we developed copper cobalt sulfide on carbon cloth (CC) using a simple and facile hydrothermal method. A vertically grown 2D sheet‐like structure of copper‐cobalt sulfide is observed using L‐cysteine as a sulfur source. An optimized ratio of copper(II) and cobalt(III) and the best sulfur source are found to boost the electrocatalytic activity of mixed metal thiospinel for OER. Several characterization techniques (XRD, Raman, FESEM, TEM, XPS, and ICP‐AES) were used to confirm phase purity, morphology, and composition of copper cobalt sulfides. We have established that 2D nanosheets of CuCo3Sz/CC exhibited superior electrocatalytic performance over bare RuO2 in 1.0 M KOH solution. It is observed that CuCo3Sz/CC need only 105 mV overpotential to generate 5 mA/cm2 current density. CuCo3Sz/CC is very stable and able to produce unaltered current density under an applied potential of 1.615 V vs. RHE for 48 h. Electrochemically active surface area calculation is performed for all catalysts to confirm higher electrocatalytic activity. The catalyst, CuCo3Sz/CC is used in a broad pH region using 0.5 M KOH, saline water, and 0.5 M Na2SO4 electrolyte solution to widen the applicability of water splitting. This work shows an avenue to develop active and durable electrocatalyst for OER without using any noble metal electrocatalyst.

Fabrication of N-doped carbon coated spinel copper cobalt sulfide hollow spheres to realize the improvement of electrochemical performance for supercapacitors

Metal sulfides with spinel structures have been considered as promising materials for supercapacitors and attracted increasing attentions of researchers over the past few years. However, inherent defects of metal sulfides such as poor electric conductivity and cyclic stability limit the practical application. Herein, we present a facile strategy to fabricate N-doped carbon coated spinel copper cobalt sulfide hollow spheres with remarkable electrochemical performance. A kind of Cu–Co coordination polymer spheres was utilized as template and metal precursor, polydopamine modified on the surface of the spheres was the source of N-doped carbon. The optimized hybrid materials exhibit high specific capacitance (1228 F g−1 at 1 A g−1) and outstanding cyclic stability (retaining 81.5% of the initial capacitance after 10000 cycles at 20 A g−1). The result demonstrates that this hybrid material is a promising electrode material to realize high performance supercapacitors.

Engineering Ternary Copper-Cobalt Sulfide Nanosheets as High-performance Electrocatalysts toward Oxygen Evolution Reaction

The rational design and development of the low-cost and effective electrocatalysts toward oxygen evolution reaction (OER) are essential in the storage and conversion of clean and renewable energy sources. Herein, a ternary copper-cobalt sulfide nanosheets electrocatalysts (denoted as CuCoS/CC) for electrochemical water oxidation has been synthesized on carbon cloth (CC) via the sulfuration of CuCo-based precursors. The obtained CuCoS/CC reveals excellent electrocatalytic performance toward OER in 1.0 M KOH. It exhibits a particularly low overpotential of 276 mV at current density of 10 mA cm−2, and a small Tafel slope (58 mV decade−1), which is superior to the current commercialized noble-metal electrocatalysts, such as IrO2. Benefiting from the synergistic effect of Cu and Co atoms and sulfidation, electrons transport and ions diffusion are significantly enhanced with the increase of active sites, thus the kinetic process of OER reaction is boosted. Our studies will serve as guidelines in the innovative design of non-noble metal electrocatalysts and their application in electrochemical water splitting

Hierarchical copper cobalt sulfides nanowire arrays for high-performance asymmetric supercapacitors

Binary transition metal sulfides are considered to be promising electrode materials for high-performance supercapacitors because of their ultrahigh electron conductivity and superior electrochemical activity compared to the unitary transition metal sulfides. In this work, copper cobalt sulfides nanowire arrays on nickel foam with different element ratios and porosities are prepared by using a two-step hydrothermal method, and their electrochemical performance is explored. Benefited from the high electrical conductivity, rich active sites and optimized microstructure, the optimized copper cobalt sulfides (CuCo2S4) electrode can achieve a ultrahigh specific capacitance of 2446.6 F·g−1 at 1 A·g−1 and favorable rate performance. The asymmetric supercapacitor assembled with the CuCo2S4 nanowire array and activated carbon (AC) electrodes displays a high energy density of 33.4 Wh·kg−1 at a power density of 751.5 W·kg−1 can be obtained. Additionally, the assembled asymmetric cell shows a favorable capacitance retention of 78% after charging and discharging for 10,000 cycles at a high current density of 4 A·g−1.

Synthesis of Hierarchically Copper Cobalt Sulfides Hollow Nanoprisms via Self-Template Route as Electrode Material for Supercapacitors

Synthesis of Hierarchically Copper Cobalt Sulfides Hollow Nanoprisms via Self-Template Route as Electrode Material for Supercapacitors

Synthesis of Ni‐Doped Copper Cobalt Sulfide Nanoparticles and its Enhanced Properties as an Electrocatalyst for Hydrogen Evolution Reaction

AbstractDeveloping high‐efficiency electrocatalysts for hydrogen evolution reaction (HER) is vitally important in electrochemical water splitting technology. Herein, ultra‐small Ni‐doped CuCo2S4 nanoparticles (NCCS NPs) are easily achieved in a single step by a facile hydrothermal method. The investigations, using powder X‐ray diffraction, X‐ray photoelectron spectroscopy, scanning electron microscopy, and TEM, reveal that the as‐prepared NCCS products are composed of a large number of uniform nanoparticles with sizes ranging from 20 to 50 nm. Triethanolamine is of vital importance for the formation of the NCCS NPs during the sulfidation process. As a promising electrocatalyst for HER, the NCCS NPs not only display a lower overpotential at 10 mA cm−2 current density than that of bare CuCo2S4 nanoparticles (CCS NPs), but also show better long‐term durability than CCS NPs during the galvanostatic electrolysis. Furthermore, Ni doping for NCCS NPs are proved to play a particular important role in the HER process. This finding provides a strategy in compositional tuning of mixed polymetallic sulfides catalysts for electrochemical hydrogen evolution.

High rate capability electrode constructed by anchoring CuCo2S4 on graphene aerogel skeleton toward quasi-solid-state supercapacitor

Designing nano-scale electrode materials has been proven to be an efficient path for enhancing the rate capability and stability of supercapacitors. Herein, a novel electrode is designed by anchoring copper cobalt sulfide (CuCo2S4) nanoparticles on the graphene aerogel (GA) via a facile solvothermal method. The CuCo2S4 particles with an average size of 21 nm can guarantee the abbreviated ion diffusion paths and the GA can ensure a conductive skeleton and prevent CuCo2S4 from agglomeration, thus promoting kinetics and efficiency of electrochemical process synchronously. As a result, the CuCo2S4/GA electrode exhibits a high specific capacitance of 668 F g−1 at a current density of 1 A g−1 along with 72% retention as the current increases to 20 A g−1, showing a decent rate capability. The measurable analysis of charge storage reveals that the surface capacitive process plays a dominant role during the electrochemical process and its proportion raises with the increase of the scan rate, resulting in excellent rate capability. Additionally, a quasi−solid−state supercapacitor is assembled by using CuCo2S4/GA composite as the free-standing electrode, which delivers an energy density of 22 W h kg−1 together with a power density of 1080 W kg−1, implying the potential application in supercapacitors.

Self‐Supporting CuCo2S4 Microspheres for High‐Performance Flexible Asymmetric Solid‐State Supercapacitors

Copper cobalt sulfide (CuCo2S4) microspheres were grown directly on a carbon cloth (CC) substrate via a facile hydrothermal synthesis route. The possible formation mechanism of flower‐like CuCo2S4 microspheres was also discussed. The resultant composite was explored as a binder‐free electrode for supercapacitors, delivering a high capacitance of 166.67 mAh g–1 at 1 A g–1, excellent rate capability (108.33 mAh g–1 at 10 A g–1) and pronounced long‐term cyclability up to 3000 cycles. A flexible solid state supercapacitor was also assembled with binder‐free electrode materials and exhibits an energy density of 17.12 Wh kg–1 at a power density of 194.4 W kg–1, and a good cycling stability with 78.4 % of initial capacity retention rate can be maintained at 1 A g–1 after 3000 cycles. In addition, the electrochemical performance of supercapacitor device is still quite stable even if it was bent 180° or twisted 150°. Two charged CuCo2S4/CC//AC supercapacitors in series can light 1 red color LED's (2 V) for 5 minutes. All these features indicate that the CuCo2S4/CC device is an excellent candidate for energy storage.

High-Performance Flexible Quasi-Solid-State Supercapacitors Realized by Molybdenum Dioxide@Nitrogen-Doped Carbon and Copper Cobalt Sulfide Tubular Nanostructures.

Flexible quasi‐/all‐solid‐state supercapacitors have elicited scientific attention to fulfill the explosive demand for portable and wearable electronic devices. However, the use of electrode materials faces several challenges, such as intrinsically slow kinetics and volume change upon cycling, which impede the energy output and electrochemical stability. This study presents well‐aligned molybdenum dioxide@nitrogen‐doped carbon (MoO2@NC) and copper cobalt sulfide (CuCo2S4) tubular nanostructures grown on flexible carbon fiber for use as electrode materials in supercapacitors. Benefiting from the chemically stable interfaces, affluent active sites, and efficient 1D electron transport, the MoO2@NC and CuCo2S4 nanostructures integrated on conductive substrates deliver excellent electrochemical performance. A flexible quasi‐solid‐state asymmetric supercapacitor composed of MoO2@NC as the negative electrode and CuCo2S4 as the positive electrode achieves an ultrahigh energy density of 65.1 W h kg−1 at a power density of 800 W kg−1 and retains a favorable energy density of 27.6 W h kg−1 at an ultrahigh power density of 12.8 kW kg−1. Moreover, it demonstrates good cycling performance with 90.6% capacitance retention after 5000 cycles and excellent mechanical flexibility by enabling 92.2% capacitance retention after 2000 bending cycles. This study provides an effective strategy to develop electrode materials with superior electrochemical performance for flexible supercapacitors.

Effect of reaction temperature on the amorphous-crystalline transition of copper cobalt sulfide for supercapacitors

Amorphous and crystalline copper cobalt sulfides are successfully synthesized via a hydrothermal method at different temperatures and researched as electrode materials for supercapacitor. The reaction mechanisms during the sulfidation and hydrothermal processes are investigated and clarified. It is demonstrated that the hydrothermal temperature is a crucial factor for the crystallinity, morphology and electrochemical performance of CuCo2S4. Among all the samples, the CuCo2S4 synthesized at 150 °C shows the highest specific capacitance of 515 F g-1 at 1 A g−1 as well as good cycling stability with ∼93.3% capacitance retention after 10000 cycles at 5 A g−1. An asymmetric device which is assembled by using optimized CuCo2S4 electrode as positive electrode and activated carbon as negative electrode material is able to deliver an ultrahigh energy density of 50.56 Wh kg−1 at a power density of 4.6 kW kg−1, and remains 20.93 Wh kg−1 at a high power density of 22.5 kW kg−1, with ∼99% capacity retention after 10000 cycles. Based on the results above, the CuCo2S4 materials prepared by our method possess a considerable potential as electrode materials for supercapacitor applications.