Nanosheet Heterostructure Research Articles

An interface engineering induced hierarchical NiCo/V2O3/C Schottky heterojunction catalyst for large-current-density hydrogen evolution reaction

A nickel foam (NF) supported NiCo/V2O3/C nanosheet heterostructure electrocatalyst benefiting from the reasonable coordination of structural engineering and interface engineering shows excellent HER activity.

Plasma synthesis of oxygen vacancy-rich CuO/Cu2(OH)3NO3 heterostructure nanosheets for boosting degradation performance.

Defect regulation and the construction of a heterojunction structure are effective strategies to improve the catalytic activity of catalysts. In this work, the rapid conversion of CuO to Cu2(OH)3NO3 was achieved by fixing nitrogen in air as NO3- using dielectric barrier discharge (DBD) plasma. This innovative approach resulted in the successful synthesis of a CuO/Cu2(OH)3NO3 nanosheet heterostructure. Notably, the samples prepared using plasma exhibit thinner thickness and larger specific surface area. Importantly, oxygen vacancies are introduced, simultaneously forming heterojunction interfaces within the CuO/Cu2(OH)3NO3 structure. CuO/Cu2(OH)3NO3 using plasma effectively degraded 96% of methyl orange within 8 min in the dark. The degradation rate is 81 and 23 times that of CuO and Cu2(OH)3NO3 using hydrothermal methods, respectively. The high catalytic activity is attributed to the large specific surface area, the abundance of active sites, and the synergy between oxygen vacancies and the strong heterojunction interfacial interactions, which accelerate the transfer of electrons and the production of reactive oxygen species (˙O2- and ˙OH). The mechanism of plasma preparation was proposed on account of microstructure characterization and online mass spectroscopy, which indicated that gas etching, gas expansion, and the repulsive force of electrons play key roles in plasma exfoliation.

Elemental sulfur supported on ultrathin titanic acid nanosheets for photocatalytic reduction of CO2 to CH4

The photocatalytic reduction of CO2 into energy-intensive hydrocarbon fuels is promising to solve environment and energy issues. Here, elemental sulfur supported on ultrathin titanic acid nanosheets (S/HTO) heterostructure is designed and synthesized by loading different weight contents of elemental S on HTO nanosheets via a simple in-situ disproportionation-assembly process. The as-designed S/HTO heterostructure not only enhances light absorption and facilitates CO2 adsorption, but also significantly promotes the interfacial charge transport, and suppresses the recombination of photogenerated charge carriers. As a consequence, the as-prepared S/HTO heterostructure exhibits enhanced performance in photocatalytic CO2 reduction under simulated solar light illumination. A CH4 yield rate of 1.92 μmol h−1 g−1 is obtained over the optimal 15S/HTO composite without the using of cocatalyst and sacrificial agent. The photoactivity is 5.4-fold and 23-fold larger than that of HTO nanosheets and blank S, respectively. In addition, the S/HTO hybrid composite also presents high stability for the production of CH4.

Edge-Site-Enriched Ti3C2Tx MXene/MoS2 Nanosheet Heterostructures for Self-Powered Breath and Environmental Monitoring

The architecture of an ammonia (NH3) monitoring system that serves as a versatile tool for real-time breath sampling and environmental gas sensing is proposed herein. By means of first-principles density functional theory (DFT) simulations, an edge-site-enriched MXene/MoS2 nanosheet heterostructure is systematically investigated and used both as a sensing material and an active layer of a hybrid tribo-/piezonanogenerator (H-TPNG). This allows combining the potential of gas sensing and energy harvesting into a single device, with benefits of self-powered monitoring of NH3. The high selectivity, reversibility, and sensitivity (47%@10 ppm) of the prepared sensor to target NH3 gas are revealed, resulting from the increased adsorption sites and improved charge transfer at the edge sites observed from DFT studies. On the other hand, the mechanical tapping and bending motions of the H-TPNG effectively stimulate the instantaneous triboelectric and piezoelectric power densities of 1604.44 and 15.62 mW/cm2, respectively. Additionally, the nanofibrous morphology of the H-TPNG introduced by the electrospinning technique provides great flexibility and conformability to the device for large-area integration of body parts. Finally, a self-powered NH3 monitoring system is assembled which demonstrates the autonomous operation of a sensor for breath analysis and environmental monitoring and could pave the way for the advancement of wearable monitors for healthcare applications.

Construction of NiS@CoFeMoO4/NF nanosheet heterostructures for efficient overall water splitting

Inexpensive and robust earth-abundant electrocatalysts with excellent electrocatalytic reaction kinetics must be developed to realize electrochemical water-splitting. In this study, nickel sulfide@cobalt iron-molybdenum oxide (NiS@CoFeMoO4) nanosheet heterostructures supported on nickel foam were fabricated. The as-built NiS@CoFeMoO4/NF with a sheet-on-sheet morphology delivered a current density of 10 mA cm−2 with a low overpotential of 72 and 200 mV for the hydrogen evolution and oxygen evolution reactions, respectively. The formation of a synergistic heterostructure between NiS and CoFeMoO4/NF via interfacial engineering facilitated the generation of a micro-mesoporous surface and modulation of the charge density at interfaces. Consequently, this configuration outperformed many non-precious-metal-based catalysts as an electrocatalyst for water oxidation.

Facile Synthesis of Co3O4/CoMoO4 Heterostructure Nanosheets for Enhanced Acetone Detection.

Although p-type semiconductors exhibit highly selective and stable chemiresistive gas sensing performances compared to conventional n-type semiconductors, their low sensitivity had long impeded their practical development. In this work, we developed highly porous Co3O4/CoMoO4 heterostructure nanosheets (NSs) with enhanced sensitivity and superior stability toward acetone gas through a facile solution-based approach with Mo-impregnated Co-based metal-organic frameworks as the starting material. The spontaneous formation of a large number of p-p heterojunctions at the Co3O4-CoMoO4 interface would facilitate the adsorption of oxygen and acetone molecules, as verified by density functional theory calculations. Consequently, experimental results showed that the Co3O4/CoMoO4 NSs have a greatly enhanced response of 8.5 toward 5 ppm acetone, which is 7.1 times higher than that of pure Co3O4 NS, without involving any noble metal catalysts. Moreover, the limit of detection of the Co3O4/CoMoO4 NSs was as low as 10 ppb. Altogether, we propose that our synthetic approach for the engineering of p-p heterojunctions is an effective strategy for the future development of highly practical and sensitive gas sensors based on p-type semiconductors.

Ni2P Nanoparticle-Inserted Porous Layered NiO Hetero-Structured Nanosheets as a Durable Catalyst for the Electro-Oxidation of Urea.

The electro-oxidation of urea (EOU) is a remarkable but challenging sustainable technology, which largely needs a reduced electro-chemical potential, that demonstrates the ability to remove a notable harmful material from wastewater and/or transform the excretory product of humans into treasure. In this work, an Ni2P-nanoparticle-integrated porous nickel oxide (NiO) hetero-structured nanosheet (Ni2P@NiO/NiF) catalyst was synthesized through in situ acid etching and a gas-phase phosphating process. The as-synthesized Ni2P@NiO/NiF catalyst sample was then used to enhance the electro-oxidation reaction of urea with a higher urea oxidation response (50 mA cm−2 at 1.31 V vs. RHE) and low onset oxidation potential (1.31 V). The enhanced activity of the Ni2P@NiO/NiF catalyst was mainly attributed to effective electron transport after Ni2P nanoparticle insertion through a substantial improvement in active sites due to a larger electrochemical surface area, and a faster diffusion of ions occurred via the interactive sites at the interface of Ni2P and NiO; thus, the structural reliability was retained, which was further evidenced by the low charge transfer resistance. Further, the Ni2P nanoparticle insertion process into the NiO hetero-structured nanosheets effectively enabled a synergetic effect when compared to the counter of the Ni2P/NiF and NiO/NiF catalysts. Finally, we demonstrate that the as-synthesized Ni2P@NiO/NiF catalyst could be a promising electrode for the EOU in urea-rich wastewater and human urine samples for environmental safety management. Overall, the Ni2P@NiO/NiF catalyst electrode combines the advantages of the Ni2P catalyst, NiO nanosheet network, and NiF current collector for enhanced EOU performance, which is highly valuable in catalyst development for environmental safety applications.

Construction of core–shell CeO2 nanorods/SnIn4S8 nanosheets heterojunction with rapid spatial electronic migration for effective wastewater purification and H2O2 production

In order to promote green development and low-carbon transformation, the development of high-performance and multi-functional photocatalysts for green chemical production and environmental remediation has become a hot research topic. In this work, a novel core–shell CeO2 nanorods/SnIn4S8 nanosheets heterostructure (COSIS) was successfully fabricated. The photocatalytic degradation of methyl orange (MO), production of H2O2 and reduction of Cr (VI) were used to evaluate the multifunctional and practical application prospects of as-prepared COSIS materials. The results showed that the photocatalytic activities of COSIS heterostructures were significantly improved compared with the original SnIn4S8 and CeO2, and the optimized COSIS2 displayed the best photocatalytic activities. The kinetic rates of MO degradation, Cr (VI) reduction and H2O2 production over COSIS2 were 10.2, 17.4 and 39.1 times than those of CeO2 and 2.5, 3.8 and 7.2 times than those of SnIn4S8, respectively. The improved photocatalytic performance could be attributed to the construction of coaxial core–shell heterostructure and synergistic effect between SnIn4S8 and CeO2, which effectively improved the charge separation efficiency. The cyclic experiments and XRD patterns before and after recycling runs over COSIS2 heterostructure confirmed its good sustainability and recycling. Finally, the direct Z-scheme CeO2 nanorods/SnIn4S8 nanosheets core–shell heterojunction was proposed to explain the photocatalytic mechanism. This work will provide reference and guidance for constructing SnIn4S8-based core–shell heterojunction and designing multifunctional photocatalysts for industrial production and environmental governance.

Tremella-Like Ni-NiO with O-Vacancy Heterostructure Nanosheets Grown In Situ on MXenes for Highly Efficient Hydrogen and Oxygen Evolution.

Electronic modulation via heterostructures or vacancies has been recently regarded as an effective strategy to improve electrocatalytic activity by optimizing the adsorption free energies of hydrogen evolution reaction (HER) or oxygen evolution reaction (OER) active intermediates during the reaction. Herein, tremella-like Ni-NiO with O-vacancy heterostructure nanosheets grown in situ on Ti3C2Tx MXenes (Ni-NiO/Ti3C2Tx MXene) are fabricated via a facile strategy. Benefitting from the heterointerfaces between Ni and NiO, the synergetic coupling effects of MXenes and Ni-NiO heterostructures, the O-vacancies, and the unique architecture, the as-prepared Ni-NiO/Ti3C2Tx MXene showed superior activity toward the HER and OER in alkaline electrolyte, only requiring overpotentials of 72 mV for the HER and 248 mV for the OER to offer 10 mA cm-2. Density functional theory (DFT) calculations revealed that Ni-NiO with O-vacancies can effectively increase the electron density around the Fermi level and modulate the Gibbs free energies of the intermediates during catalytic reactions, thus accelerating the reaction kinetics.

One-Step Epitaxial Growth of Multilayer MoS2/SnS2 Vertical Nanosheets for High-Performance Photodetectors

Two-dimensional (2D) van der Waals heterostructures have aroused widespread interest in basic research and device construction because of their unique physical properties and better device performance. Previous studies often focused on vertical bilayer heterostructures composed of two distinct monolayer 2D materials using chemical vapor deposition (CVD) processes. Here, a KI-assisted confined-space CVD method is reported to synthesize multilayer MoS2/SnS2 vertical heterostructure nanosheets composed of monolayer MoS2 and multilayer SnS2. The optical characterizations reveal a clear interface between monolayer MoS2 and multilayer SnS2 as well as the vertical heterostructure. Photodetectors based on the as-grown MoS2/SnS2 heterostructure nanosheets can obtain a maximum responsivity of 9611 A/W under visible light illumination. Meanwhile, the minimum response time is about 510 μs. The ultrasensitive photoresponse may be related to the higher light absorption of such multilayer SnS2. This work not only provides an approach to construct multilayer 2D heterostructure nanosheets but also demonstrates their potential advantages in the application of high-performance photodetectors.

Surface engineering of Ni2P/CoP nanosheet heterojunctions by the formation of F-doped carbon layers for boosting urea-rich water electrolysis

It's highly desirable but still challenging to design bifunctional non-noble metal electrocatalysts for the hydrogen evolution reaction (HER) and urea oxidation reaction (UOR) with high activity and boosted mass transport, especially under large-current densities. Hence, a novel 3D reticular heterostructure nanosheet arrays are fabricated (Ni2P/CoP/P,F–C) through coupling the F-doped carbon to realize urea-rich water electrolysis. The interface of carbon doping F can effectively enhance the conductivity and stability of Ni2P/CoP heterojunctions along with possible changes in surface hydrophobicity to accelerate release of generated bubbles under large-current densities. Benefiting from tailored d-band center of CoP nanosheet arrays and well-designed hydrophilic-superaerophobic feature, the elaborated Ni2P/CoP/P,F–C electrode shows brilliant electrocatalytic HER (198 mV) and UOR (251 mV) performance at 100 mA cm−2 current density. Meanwhile, the assembled alkaline urea-rich water electrolyzer with Ni2P/CoP/P,F–C as both the cathode and anode present ultralow cell voltages of 1.57 V to achieve 100 mA cm−2 with long-time stability. This work will promote research interest in material design for energy conversion technologies and urea-assisted hydrogen production.

Selective detection of ethanol at low concentration by ZnO@ZIF-8 porous nanosheets

Effectively improve the sensitivity of semiconductor gas sensors, reduce the working temperature and improve its detection ability at low concentrations are priority for practical applications. However, the design of appropriate sensing materials has become a great challenge. Herein, two-dimensional (2D) ZnO@ZIF-8 porous nanosheets (PNSs) heterostructures are prepared via a facile solvothermal method for ethanol detection. ZIF-8 can be used as a “breathable” support/filter layer to reduce self-accumulation of ZnO PNSs. ZnO@ZIF-8–24 exhibits an enhanced response (Ra/Rg=58) with high selectivity (SEthanol/SInterfering values ranged from 2.1 to 25.2) toward 50 ppm ethanol at 240 °C compared to ZnO. Meanwhile, ZnO@ZIF-8 (Ra/Rg=7.2) has better response than ZnO (Ra/Rg=2.8) at low concentration (5 ppm).The enhancement is ascribed to the increased exposure of active sites due to the inhibition of self-stacking of two-dimensional porous nanosheets by ZIF-8 nanoparticles. Furthermore, the heterostructures can strengthen the electron transfer and adsorption of ethanol molecules on ZIF-8. Thus, our research provides a new approach for the application of 2D heterostructures in gas sensing.

Fe7Se8@Fe2O3 heterostructure nanosheets as bifunctional electrocatalyst for urea electrolysis

Water electrolysis for producing hydrogen is considered to be the most feasible means to develop new green energy. Compared with above, urea electrolysis can improve energy conversion efficiency by introducing urea, and can also be used for purification of wastewater rich in urea. In this paper, a bifunctional electrocatalyst with heterostructure, namely Fe7Se8@Fe2O3 nanosheets supported on nickel foam, were synthesized for the first time through typical hydrothermal and partial oxidation processes. Iron cation promotes electron transfer and adjusts electron structure under the synergistic action of selenium and oxygen anion, thus achieving excellent catalytic activity of urea electrolysis. In an alkaline solution of 1 M KOH with 0.5 M urea, the Fe7Se8@Fe2O3/NF catalyst can drive the current density of 10 mA cm−2 with requiring only potential of 1.313 V and overpotential of 141 mV for urea oxidation reaction (UOR) and hydrogen evolution reaction (HER), respectively. What is noteworthy is that Fe7Se8@Fe2O3/NF heterostructure is used as bifunctional electrocatalyst to form urea electrolyzer device, which only needs potential of 1.55 V to drive current density of 10 mA cm−2, which is one of the best catalytic activities reported so far, and the electrode couple showed remarkable stability for 15 h. Density functional theory shows that the Fe7Se8@Fe2O3/NF material exhibits the minimum Gibbs free energy for the adsorption of hydrogen. This work provides a new method for exploring novel and environmentally friendly bifunctional electrocatalysts for urea electrolysis.

Sandwich-like GaN/MoSe2/GaN heterostructure nanosheet: A First-principle study of the structure, electronic, optical, and thermodynamical properties

Due to the wide range of applications of two-dimensional heterostructures in photocatalysis, electronics, and optoelectronics, research on these materials has received considerable interest. This paper provides a systematic understanding of the sandwich-like GaN/MoSe2/GaN heterostructure nanosheet to explore geometrical structures and electronic, optical, and thermodynamical properties using a density functional theory. As per the band structure analysis, the heterostructure is a type-II semiconductor with a direct band-gap of 1.36 eV. The optical properties of the nanosheet in different polarization directions were studied. The work function of the heterostructure shows 5.10 eV, which is smaller than the constituent nanosheets. The phonon dispersion curves do not show a negative acoustic band that shows the stability of the studied nanosheets. The alignment of the band structures, charge difference and generated electric field at the vdW heterostructure interface advantage constrain photogenerated electron-hole recombination, enabling improved optical characteristics in the ultraviolet-visible and near-infrared spectroscopy regions, indicating the studied heterostructure can be employed in photovoltaic, photocatalytic, and optical devices.

Synergic effect of Fe-doping and Ni3S2/MnS heterointerface to boost efficient oxygen evolution reaction

The high overpotential of oxygen evolution reaction (OER) is the main limitation of electrolytic water splitting efficiency for hydrogen production. Herein, Fe doped Ni3S2/MnS heterostructured nanosheets were grown on Ni foam (Fe-Ni3S2/MnS@NF) via a simple one-step solvothermal reaction. As-synthesized Fe-Ni3S2/MnS@NF exhibits excellent OER electrocatalytic activity in 1 M KOH, with an extremely low overpotential of 259 mV at 50 mA cm−2 as well as a small Tafel slope (39 mV dec−1), much better than Ni3S2-, Fe-doped Ni3S2-, and Ni3S2/MnS- nanosheets grown on NF. Results clearly reveal that the better electrocatalytic performance of Fe-Ni3S2/MnS@NF than its rivals is mainly due to the synergistic effect of Fe-doping and Ni3S2/MnS heterojunctions. In details, heterojunction combination with Fe-doping not only improves the conductivity of catalysts but also modulates the electronic configuration of active sites and optimizes the adsorption capacity of oxygen-containing intermediates, thus achieving rapid reaction kinetics and high electrocatalytic performance. This work provides insights into the synergistic regulation of electrocatalytic activity of non-noble catalysts toward high efficiency energy conversion.

In-situ sulfidation-derived three-dimensional cobalt sulfide nanoflower/graphene nanosheet hybrid for ultrasensitive room-temperature NO2 gas sensor

Two-dimensional (2D) nanosheets show great potential for gas sensing, but they can hinder the penetration of gas molecules and lead to deteriorated sensing performances. Hence, construction of 2D nanosheet-based gas sensing materials with unique structures is desirable for high-performance gas sensing. Herein, a three-dimensional (3D) binary nanosheet heterostructure based on 3D cobalt sulfide (CoS) nanoflower/graphene nanosheet hybrid was constructed for room-temperature NO2 gas sensing. The 3D CoS/reduced graphene oxide (rGO) hybrid derived from a mixture of Co3O4 nanoflowers and graphene oxide nanosheets was facilely formed via in-situ sulfidation and reduction processes. The resistance response of as-assembled gas sensor based on 3D CoS nanoflower/graphene nanosheet hybrid to 1 ppm NO2 was 39.7%, which was 4.2 and 3.1 times higher than that of CoS and rGO sensors, respectively. A response as high as 10.5% was achieved even when the device was exposed to NO2 gas with a low concentration of 50 ppb. Furthermore, the hybrid device exhibited linear response characteristic, high selectivity, good repeatability, as well as long-term stability. Overall, the proposed design strategy together with the as-constructed structures can pave the way for the development of high-performance gas sensors based on graphene hybrids.

Asymmetric interfacial oxygen sites of porous CeO2-SnO2 nanosheets enabling highly sensitive and selective detection of 3-hydroxy-2-butanone biomarkers

The local environment of active sites and the number of oxygen vacancies can greatly affect the reactivity of semiconductor metal oxides (SMOs). However, rare work has been reported to investigate the relationship between the state of oxygen vacancies and sensing performance of SMOs. Herein, a series of porous CeO2-SnO2 hetero-structure nanosheets with fine modulation of the local environment active sites and oxygen defect activity have been successfully constructed. We have investigated their sensing performance towards 3-hydroxy-2-butanone, which is a biomarker of food pathogenic microbe Listeria monocytogenes. We found that the amount of asymmetric Ce-O-Sn sites rather than total oxygen vacancies amount of CeO2/SnO2 materials can greatly affect their sensing performance. Impressively, the porous CeO2/SnO2-400 nanosheets, which possessed abundant active O-(ad) species originated from the asymmetric Ce-O-Sn sites, exhibited high sensitivity (Ra/Rg=637.94 to 50 ppm), fast response (29 s) and recovery (172 s), excellent selectivity and high stability toward 3-hydroxy-2-butanone at a working temperature of 160 °C. Both the surface O-(ad) species associated with the asymmetric oxygen sites and porous nanosheet hetero-structure contribute to the enhanced gas adsorption and diffusion process, further boosting their sensing performance. Our work provides new sights for identification of active sites in sensing materials as well as paves the way for detection of pathogenic microbes in food.

Two-dimensional CoP-Ni2P heterostructure nanosheets intertwined with carbon nanotubes as catalysts for enhanced hydrogen generation and urea oxidation

Electrocatalytic water splitting is an efficient way to provide green energy hydrogen (H2), and it is a challenge to prepare high-efficiency and inexpensive electrocatalysts. In this work, we constructed two-dimensional (2D) CoP-Ni2P heterostructure nanosheets intertwined with carbon nanotube (CoP-Ni2P/CNT) as bifunctional electrocatalysts with excellent performance. The CoP-Ni2P/CNT exhibits the outstanding HER (an overpotential of 82 mV at 10 mA cm−2 and Tafel slope of 62.6 mV dec−1) and OER (an overpotential of 210 mV at 10 mA cm−2 and Tafel slope of 97.4 mV dec−1) activities. The optimal electrocatalytic performance of the CoP-Ni2P/CNT are ascribed to the following factors: i) the introduction of CNTs into electrocatalysts is helpful to reduce excessive aggregation of nanosheets and enhance the electron transport rate; ii) the 2D nanosheet structure and interface designing of CoP-Ni2P/CNT expose more active sites, which are beneficial to enhance electrocatalytic performance toward HER and OER. In a two-electrode system, the cell voltage is 1.39 V to reach 10 mA cm−2 after adding 0.1 M urea into 1 M KOH electrolyte. This obviously low voltage implies the feasibility of realizing energy-saving hydrogen production and urea degradation. All these results reveal the CoP-Ni2P/CNT is a promising bifunctional electrocatalyst toward practical application.

Cu/CuOx In-Plane Heterostructured Nanosheet Arrays with Rich Oxygen Vacancies Enhance Nitrate Electroreduction to Ammonia.

The artificial ammonia synthesis via electrochemical nitrate reduction has met increasing research interest, but it is still necessary to develop advanced catalysts with high nitrate-to-ammonia capability. Herein, we propose and demonstrate a one-step method to construct binder-free Cu foam-supported oxygen vacancy-rich Cu/CuOx in-plane heterostructured nanosheet arrays (Cu/CuOx/CF). In addition to exposing ample active sites, the two-dimensional nanosheet morphology greatly facilitates the mass/charge-transfer process during electrocatalysis. Besides, the in-plane heterojunctions and rich oxygen vacancies induced synergistic effect can modulate the electronic structure of active sites and thus tune the adsorption properties of the reactant intermediates and inhibit the formation of undesirable byproducts, which is conducive to the further improvement of nitrate reduction activity. As a result, these advantages endow the Cu/CuOx/CF with superior performance for ammonia synthesis via nitrate electroreduction, achieving high ammonia selectivity (95.00%) and Faradaic efficiency (93.58%).

Preparation of nanosheets of Ni5P2@Ni9S8/CoS1.097 heterostructure for aqueous asymmetric supercapacitors with high electrochemical performance

In recent years, transition metal sulfides, especially nickel-cobalt sulfide materials play a crucial role for supercapacitor applications. In this work, the Ni5P2@Ni9S8/CoS1.097 (Ni-P@NCS) core-shell material has been synthesized by simply phosphating the nickel mesh and subsequent electrodeposition of NCS to obtain a nanosheet heterostructure on nickel foam. The Ni-P@NCS composite material has a higher gravimetric capacitance of 2445.7 F g−1 than pure Ni-P of 1116.6 F g−1 and NCS materials of 1104.3 F g−1 at 1 A g−1. At the same time, Ni-P@NCS electrode yields excellent cycling stability (91.4% capacitance retention after 5000 charge–discharge cycles). An asymmetric supercapacitor (ASC) device assembled from Ni-P@NCS and activated carbon electrodes can deliver a highest energy/power density of 42.8 Wh kg−1/799.8 W kg−1, with 94.3% capacitance retention after 10,000 cycles at 5 A g−1. The improvement of electrochemical performance makes it possible to use it as an electrode material.