Cathode Material For Hybrid Supercapacitors Research Articles

Interconnected CoNi-Se Hollow Flakes through Reduced Graphene Oxide Sheets as a Cathode Material for Hybrid Supercapacitors.

Achieving a high energy density and long-cycle stability in energy storage devices demands competent electrochemical performance, often contingent on the innovative structural design of materials under investigation. This study explores the potential of transition metal selenide (TMSe), known for its remarkable activity, electronic conductivity, and stability in energy storage and conversion applications. The innovation lies in constructing hollow structures of binary metal selenide (CoNi-Se) at the surface of reduced graphene oxide (rGO) arranged in a three-dimensional (3D) morphology (CoNi-Se/rGO). The 3D interconnected rGO architecture works as a microcurrent collector, while porous CoNi-Se sheets originate the active redox centers. Electrochemical analysis of CoNi-Se/rGO based-electrode reveals a distinct faradic behavior, thereby resulting in a specific capacitance of 2957 F g-1 (1478.5 C g-1), surpassing the bare CoNi-Se with a value of 2149 F g-1 (1074.5 C g-1) at a current density of 1 A g-1. Both materials exhibit exceptional high-rate capabilities, retaining 83% of capacitance at 10 A g-1 compared to 1 A g-1. In a two-electrode coin cell system, the device achieves a high energy density of 73 Wh kg-1 at a power density of 1500 W kg-1, stating an impressive 90.4% capacitance retention even after enduring 20,000 cycles. This study underscores the CoNi-Se/rGO composite's promise as a superior electrode material for high-performance energy storage applications.

Hierarchical nickel hydroxide hydrate assembled by ultrathin nanosheets for high-performance hybrid supercapacitors

Due to its unique nature, nickel hydroxide is an attractive cathode material for hybrid supercapacitors (HSCs). A facile solvothermal strategy was proposed to synthesize hierarchical nickel hydroxide hydrate (HNHH) assembled by ultrathin nanosheets. The reaction temperature (T) has a dramatic effect on the morphology and specific surface area (SSA). The prepared HNHH-T could offer large SSAs from 175.3 to 287.2 m2g−1 with rich mesopores at 3.3–4.3 nm, which are favorable for boosting the electrochemical activity. Among diverse HNHH-T electrodes, HNHH-120 delivered a maximum specific capacity of 718.0 C g−1 at 0.5 A g−1. Furthermore, the assembled HNHH-120//activated carbon (AC) HSC could acquire 95.0 F g−1 at 0.5 A g−1. Strikingly, this HSC could deliver 35.9 Wh kg−1 at 412.5 W kg−1 with robust cycle durability (82.6% after 15,000 cycles at 3 A g−1). Moreover, an HNHH-120//AC device can operate a micro-fan for 54 s, demonstrating its real application prospect. The dazzling energy storage capability of HNHH-120 is mainly thanks to its large SSA and rich mesopores.

Perovskite rare earth porous hollow microspheres of SmFeO3/MWCNT battery type asymmetric hybrid supercapacitors

The rapid advancements made by science and technology in the present world are astonishing and have a way of stimulating our imagination. Modern research centres on search for unique cathode electrodes to improve energy density in hybrid supercapacitors (HSCs). A battery-type perovskite rare earth-based SmFeO3/MWCNT electrode is being investigated as cathode electrode for future-generation energy storage devices. Herein, perovskite rare earth-based metal oxides and its carbon composites (SmFeO3, SmFeO3/GC,SmFeO3/MWCNT) are flourishingly synthesized via one-step solvothermal technique as cathode materials for hybrid supercapacitors. The asymmetric solid-state supercapacitor SmFeO3/MWCNT//CNT device is constructed with an excellent 216.68 F/g specific capacitance, 67.71 Wh/kg energy and 749.97 W/kg power density at 1 A/g current density. An improved cycling performance of 79.83% capacity retention and 99.84% coulombic efficiency after 20000 long-cycles is reported. This work revealed that SmFeO3/MWCNT//CNT AHSSCs offer boundless ability as good electrode for practical energy storage applications.

Amorphous nanosheets constructed nickel cobalt hydroxysulfide hollow spheres as cathode materials for hybrid supercapacitors

Tailoring architecture and multi-composition of electrode materials via a facile and cost-effective strategy are highly favorable to optimize physiochemical properties for developing energy storage devices. Herein, hierarchical nickel cobalt hydroxysulfide hollow spheres decorated with amorphous nanosheets and dual-ligands (denoted as NiCo-DHS) are synthesized through hydrolysis of self-templating metal alkoxides, followed by room-temperature anionic exchange process. The resultant dual-ligands hydroxysulfide possesses weak metallicity, reduced band gap and enhanced conductivity owing to the electronic regulation of the formed M−OH/S bonds. Additionally, the nanosheet-constructed amorphous structure contributes to accelerating ions diffusion and enlarging specific surface area, further exposing more active sites to enrich redox reactions. Benefiting from the compositional and structural superiorities, the optimized NiCo-DHS-12 electrode presents desirable electrochemical performance, including high specific capacity of 973.6 C g−1 (1 A g−1) and stable durability over 8000 cycles with a small capacity loss of 7.4 % at 10 A g−1. Moreover, the hybrid device assembled with NiCo-DHS-12 and porous activated carbon delivers an energy density of 65.91 Wh kg−1 at a power density of 0.89 kW kg−1 and considerable cycling stability. These encouraging results demonstrate a simple and reliable approach in constructing high-performance electrode materials for advanced supercapacitors in potential.

Hierarchical Nanocages Assembled by NiCo-Layered Double Hydroxide Nanosheets for a High-Performance Hybrid Supercapacitor.

Layered double hydroxides (LDHs) have attracted broad attention as cathode materials for hybrid supercapacitors (HSCs) because of their ultrahigh theoretical specific capacitance, high compositional flexibility, and adjustable interlayer spacing. However, as reported, specific capacitance of LDHs is still far below the theoretical value, inspiring countless efforts to these ongoing challenges. Herein, a hierarchical nanocage structure assembled by NiCo-LDH nanosheet arrays was rationally designed and fabricated via a facile solvothermal method assisted by the ZIF-67 template. The transformation from the ZIF-67 template to this hollow structure is achieved by a synergistic effect involving the Kirkendall effect and the Ostwald ripening process. The enlarged specific surface area co-occurred with broadened interlayer spacing of LDH nanosheets by finely increasing the Ni concentration, leading to synchronous improvement of electron/ion transfer kinetics. The optimized NiCo-LDH-210 electrode displays a maximum specific capacitance of 2203.6 F g-1 at 2 A g-1, excellent rate capability, and satisfactory cycling stability because of the highly exposed active sites and shortened ion transport paths provided by vertically aligned LDH nanosheets together with the cavity. Furthermore, the assembled HSC device achieves a superior energy density of 57.3 Wh kg-1 with prominent cycling stability. Impressively, the design concept of complex construction derived from metal-organic frameworks (MOF) derivatives shows tremendous potential for use in energy storage systems.

Free-standing 3D core-shell architecture of Ni3S2@NiCoP as an efficient cathode material for hybrid supercapacitors

The design and discovery of free-standing hybrid electrode materials with large absolute capacity and high cycling stability for energy storage become desirable and are still challenging. In this work, we demonstrate that the hybrid supercapacitor (HSC) device is assembled by 3D core–shell hierarchical nanorod arrays of Ni3S2@NiCoP nanocomposite for the first time. The Ni3S2@NiCoP nanocomposite is successfully synthesized through a facile stratagem containing hydrothermal process and the subsequent electrodeposition method. The 3D architecture of Ni3S2@NiCoP hybrid electrode composed of vertically aligned “hyperchannel” 1D Ni3S2 nanorods and highly conductive interconnected 2D nanosheets of NiCoP is beneficial to fast electron transfer kinetics, thus leading to enhancing the ionic and electronic conductivity, kinetics of redox reaction, and synergistic behavior of active species. The fabricated HSC device with Ni3S2@NiCoP electrode delivers outstanding areal capacity of 109 µAh cm−2 at a current density of 1 mA cm−2, brilliant energy density of 74.9 Wh kg−1 at a power density of 700 W kg−1, and prominent cyclic performance of 92% capacity retention even after 144-h floating test. This work demonstrates that the core–shell hierarchical nanorod arrays of Ni3S2@NiCoP can be viewed as one of the novel battery-type electrode materials for high-performance HSCs.

Novel bouquet-like cobalt phosphate as an ultrahigh-rate and durable battery-type cathode material for hybrid supercapacitors

Red phosphorus (RP) is beneficial to industrialization due to its rich resources, chemical stability and environmental friendliness. However, the low electronic conductivity and large volume expansion limit its application for energy storage. Herein, we first used RP to prepare a novel bouquet-like Co3(HPO4)2(OH)2 by the hydrothermal approach as cathode materials for hybrid supercapacitors (HSC), which delivered a large specific capacity (119.2 mA h g−1 at 1 A g−1), a superb rate capability (83.6 mA h g−1 at 100 A g−1) and a splendid electrochemical stability (92% capacity retention after 5000 cycles at 10 A g−1). Furthermore, a novel HSC device assembled with Co3(HPO4)2(OH)2 as the cathode, porous carbon (PC) as the anode showed a high energy density of 44.6 W h kg−1 and a remarkable power density of 33.75 kW kg−1, along with an exceptional cyclic performance (91.8% capacity retention after 10,000 cycles at 3 A g−1). This study not only develops a novel type of high-performance battery-type cathode material, but also provides a new idea for the industrial application of RP.

Mn-dopant induced Octahedral Configuration Strongly Stabilizes Ni12P5 Nanowires for Battery-Supercapacitor Hybrid Devices

Transition metal phosphides (TMPs) have recently emerged as an important type of electrode materials for supercapacitors due to their intrinsically outstanding specific capacity and high conductivity. Herein, we report Mn doped Ni12P5 nanowires (Mn-Ni12P5-3) as an advanced cathode material for hybrid supercapacitors, which delivers a high specific capacity of 808 C g−1 at 1 A g−1 (560 C g−1 at 10 A g−1) and good cyclic stability (capacity retention of 87% after 1000 cycles at 10 A g−1). Meanwhile, the First-principle Calculation results reveal that the Mn-doping can form an octahedral supporting structure between Mn atoms and P atoms to enhance the structure stability. The assembled Mn-Ni12P5-3//AC hybrid device demonstrates good capacity retention of 67.3% after 5000 cycles at 2 A g−1. This research brings a new implication to the development of supercapacitors.

Bamboo Leaves as Sustainable Sources for the Preparation of Amorphous Carbon/Iron Silicate Anode and Nickel–Cobalt Silicate Cathode Materials for Hybrid Supercapacitors

Bamboo Leaves as Sustainable Sources for the Preparation of Amorphous Carbon/Iron Silicate Anode and Nickel–Cobalt Silicate Cathode Materials for Hybrid Supercapacitors

Heterostructured NiSe2/CoSe2 hollow microspheres as battery-type cathode for hybrid supercapacitors: Electrochemical kinetics and energy storage mechanism

Constructing heterostructures can adjust the electronic structure and cause the interfacial charge redistribution to promote the reaction kinetics. Besides, metal selenides as emerging battery-type cathode materials for hybrid supercapacitors (HSCs) have recently attracted increasing interests. However, the reasonable design and fabrication of heterostructured bimetallic selenides hollow microspheres, especially the theoretical explanation of their electrochemical reaction processes and energy storage mechanisms, are scarcely explored. Herein, the heterostructured NiSe2/CoSe2 hollow microspheres are prepared via one-pot hydrothermal treatment and their energy storage mechanisms are proved with experimental and theoretical analyses. Meanwhile, the charge redistribution at the heterogeneous phase boundaries is authenticated by density functional theory (DFT) calculations. Benefiting from the abundant heterogeneous phase interfaces, unique hollow heterostructure and synergistic effect, the heterostructured NiSe2/CoSe2 hollow microspheres exhibit expected electrochemical properties, particularly admirable rate capability. Moreover, a HSC device is assembled based on the heterostructured NiSe2/CoSe2 hollow microspheres cathode, displaying a superior energy density (53.7 Wh kg−1), an extremely high power density (26.1 kW kg−1) and a preeminent cycle stability. This work reveals the energy storage mechanisms of selenide and the charge redistribution of heterojunctions, which can provide a meaningful reference for constructing high-rate heterobimetallic selenide hollow microspheres with abundant phase boundaries.

NiCo2S4/nitrogen and sulfur dual-doped three-dimensional holey-reduced graphene oxide composite architectures as high-rate battery-type cathode materials for hybrid supercapacitors

Battery-type electrode materials have recently been considered as a new class of high-capacity cathode materials for construction of hybrid supercapacitors, however, their low electrochemical kinetics prevent the practical application. Here, the NiCo2S4/nitrogen and sulfur dual-doped three-dimensional (3D) holey-reduced graphene oxide (NiCo2S4/N, S-HRGO) composite architectures were synthesized via a two-step hydrothermal approach. Thanks to the introduction of 3D interconnected and highly conductive holey-reduced graphene oxide with mesopore-rich structure providing fast electron/ion transport, the as-resulted NiCo2S4/N, S-HRGO composite achieves enhanced supercapacitive performances, especially exceptional rate capability compared to the pure NiCo2S4 and NiCo2S4/nitrogen and sulfur dual-doped reduced graphene oxide (NiCo2S4/N, S-RGO). The NiCo2S4/N, S-HRGO composite shows a specific capacity of 184.2 mAh g−1 at 1 A g−1, and still maintains a high specific capacity of 119.5 mAh g−1 even at 50 A g−1. The excellent rate capability of the composite can be illustrated by in-depth kinetic analysis based on the calculated diffusion coefficient and charge contribution ratio. Furthermore, a hybrid supercapacitor utilizing NiCo2S4/N, S-HRGO and N, S, P tri-doped holey-reduced graphene oxide (N, S, P-HHGO) respectively as the cathode and anode is further constructed, showing a satisfactory energy density (35.4 Wh kg−1), high power density (15.0 kW kg−1) and good cycle durability.

Unveiling one-dimensional mixed-metallic oxysulfide nanorods as an advanced cathode material for hybrid supercapacitors

Mixed-metallic oxyphosphides and oxysulfides are prominent electrode candidates for energy storage devices owing to the synergistic benefits of metal oxides and metal sulfides. Herein, we explore nickel-molybdenum oxyphosphides and oxysulfides (NMOP/NMOS) by a one-step hydrothermal technique, followed by an anion exchange process. As a result, the materials consist of one-dimensional nanorods (1D NRs) which promote charge transportation. Both the materials with 1D NR morphology exhibit superior electrochemical performance to the nickel-molybdenum oxides (NMO) NRs due to the incorporation of phosphorus and sulfur anions. Particularly, the NMOS material demonstrates better specific capacity (38.3 mA h/g, 338.7 F/g) compared with the NMO and NMOP materials. The feasibility of NMOS NRs as a cathode material is explored by fabricating the hybrid supercapacitor (HSC). By exploiting an intriguing feature of NMOS (cathode) and activated carbon (anode) materials, the HSC delivers maximum energy and power densities of 58.9 W h/kg and 3502.5 W/kg, respectively. An HSC shows excellent cycling stability even after 10,000 cycles (90.6% retention). The suitability of HSC in real-time applications is also verified by powering various electronic components. This work promotes the rational design of novel mixed-metallic oxysulfides-based electrode materials with beneficial morphologies for high-capacity SCs.

Nickel–zinc sulfide nanocomposite thin film as an efficient cathode material for high-performance hybrid supercapacitors

Nickel–Zinc Sulfide nanocomposite (Ni–ZnS) thin film was prepared by RF magnetron co-sputtering method on a stainless steel substrate, which is used as the cathode material for hybrid supercapacitor. The as-prepared Ni–ZnS nanocomposite thin films exhibit a hexagonal structure with uniform morphology. The electrochemical results show that the Ni–ZnS nanocomposite thin film electrode exhibited a higher specific capacity when compared to the ZnS thin film. The Ni–ZnS-3 electrode has the highest specific capacity of 134 C g−1 (67 mC cm−2) at a scan rate of 10 mV s−1 with excellent cycling stability (10% loss of its initial specific capacity) even after 3500 cycles. The obtained results reveal that nickel doping has the significant effect on the electrochemical performance of zinc sulfide material and the as-fabricated material can be used as a potential positive electrode for hybrid supercapacitors.

Graphitic nanofibers decorated with Ni3S2 interlaced nanosheets as efficient binder-free cathodes for hybrid supercapacitors

In this current work, we successfully decorated free-standing conductive functionalized graphitic nanofibers (GNFs) with interlaced Ni3S2 nanosheets (designated as GNFs@Ni3S2) by using a facile pulse-reversal deposition technique, and employed the GNFs@Ni3S2 composite as an efficient binder-free cathode material for hybrid supercapacitors (HSCs) for the first time. According to the results of the material characterizations, it confirmed that that surface of the GNFs was evenly deposited with Ni3S2 nanosheets, and the resultant composite was in fibrous nanostructure. On the basis of the series of electrochemical measurements, the GNFs@Ni3S2 composite electrode revealed almost three times larger discharge capacity than the pristine Ni3S2 electrode, and exhibited superior rate capability. Moreover, a HSC device based on the GNFs@Ni3S2 cathode delivered an impressive specific capacity of 34.6 mAh g−1 at 1 A g−1 and the maximum energy density of 44.2 Wh kg−1 at a power density of 1.2 kW kg−1. Most importantly, the HSC retained 68.9% of its initial capacity after 5000 consecutive charge/discharge cycles at a current density of 4 A g−1. The remarkable electrochemical performance of the binder-free GNFs@Ni3S2 composite electrode makes it to be regarded as one of the potential cathode materials for high-performance HSCs.

3D interconnected ultrathin cobalt selenide nanosheets as cathode materials for hybrid supercapacitors

3D interconnected ultrathin CoSe nanosheets are prepared via a hydrothermal synthesis method and utilized as superior battery-like electrode material for the first time. Due to the features of the unique 3D interconnected ultrathin nanosheets with a large BET specific surface area, superior mesoporous structure and good electrical conductivity, the as-resulted 3D interconnected ultrathin CoSe nanosheets manifests a high specific capacity of 70.6 mAh g−1 at 1 A g−1 and remarkable rate performance with 52.8% of capacity retention rate at 100 A g−1 compared with 1 A g−1. Furthermore, a novel aqueous hybrid supercapacitor is assembled by employing 3D interconnected ultrathin CoSe nanosheets and activated carbon as the cathode and anode, respectively. The assembled hybrid device displays a specific energy of 18.6 Wh kg−1 at a specific power of 750 W kg−1 and outstanding cycling life with 95.4% of the initial capacity retention for 20000 cycles at 5 A g−1. These results imply that the unique 3D interconnected ultrathin CoSe nanosheets can be considered as highly potential candidate electrode materials for hybrid supercapacitors.

Cathode Materials for Hybrid Supercapacitors Based on Ozonated Reduced Graphene Oxide

A carbon material capable of reversible electrochemical oxidation and reduction with relatively high electrical conductivity was prepared by ozonation of thermally reduced graphene oxide. The specific discharge energy for such materials used in lithium ion electrochemical cell cathodes with non-aqueous electrolytes (LP-71) can reach 540 W h/kg at 40 mA/g current, while the average specific discharge power is 11.5 kW/kg at 5 A/g current. The specific charge after 2500 charge/discharge cycles at 5 A/g current was at a level of 93% of the initial value. The obtained materials appear promising for the design of new electricity storage systems.

Rational design of forest-like nickel sulfide hierarchical architectures with ultrahigh areal capacity as a binder-free cathode material for hybrid supercapacitors

The forest-like NiS hierarchical architectures demonstrated superior electrochemical performance with excellent cycling stability.

Ni-Co Binary Hydroxide Nanotubes with Three-Dimensionally Structured Nanoflakes: Synthesis and Application as Cathode Materials for Hybrid Supercapacitors.

Nickel-cobalt binary hydroxide nanotubes were fabricated by a facile synthetic approach by using Cu2 O nanowires as sacrificial templates. The surface morphology of the binary hydroxide nanotubes can be easily controlled by adjusting the molar ratio of Ni to Co. With increasing Co content, the surfaces of the nanotubes tend to form hierarchical nanoflakes. The obtained nanotubes with high specific surface area exhibit typical battery-like electrochemical behavior. Among them, Ni-Co hydroxide nanotubes with Ni:Co=48:52 showed outstanding electrochemical characteristics, with a specific capacity of 209.9 mAh g-1 at 1 Ag-1 and remarkable cycling stability with 84.4 % capacity retention after 10 000 cycles at 20 A g-1 . With the advantages of their unique nanostructure and the synergistic effect of the two elements, the Ni-Co binary hydroxide nanotubes are expected to be effective potential cathode materials for hybrid supercapacitors.

Copolymers of aniline and 2-aminoterephthalic acid as a novel cathode material for hybrid supercapacitors

A new polyaniline based co-polymer nanorod with excellent electrochemical performance is used as a novel cathod material for hybrid super capacitor.

An electrodeposited graphite oxide/cobalt hydroxide/chitosan ternary composite on nickel foam as a cathode material for hybrid supercapacitors

In this paper, we report the development of a graphite oxide (GO)/cobalt hydroxide (Co(OH)2)/chitosan composite to be used as a cathode material for hybrid supercapacitors.