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Interior and surface synergistic modifications can endow the photocatalytic reaction with tuned photogenerated carrier flow at the atomic level. Herein, a new class of 2D/2D SnNb2O6/Ni-doped ZnIn2S4 (SNO/Ni-ZIS) S-scheme heterojunctions is synthesized by a simple hydrothermal strategy, which was used to evaluate the synergy between interior and surface modifications. Theoretical calculations show that the S-scheme heterojunction boosts the desorption of H atoms for rapid H2 evolution. As a result, 25% SNO/Ni0.4-ZIS exhibits significantly improved PHE activity under visible light, roughly 4.49 and 2.00 times stronger than that of single ZIS and Ni0.4-ZIS, respectively. In addition, 25% SNO/Ni0.4-ZIS also shows superior structural stability. This work provides advanced insight for developing high-performance S-scheme systems from photocatalyst design to mechanistic insight.
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Improving greatly the separation efficiency of interfacial charge carrier is a major challenge in photocatalysis. Herein, a new class of C60 -mediated NH2 -MIL-125(Ti)/Zn0.5 Cd0.5 S S-scheme heterojunction with enhanced interfacial charge carrier separation is designed and synthesized. The constructed S-scheme heterojunction thermodynamically favors photocatalytic H2 evolution because of the large driving force resulting from its strong redox abilities. As a consequence, the optimum proportion of C60 -mediated NH2 -MIL-125(Ti)/Zn0.5 Cd0.5 S S-scheme heterojunction displays comparable H2 evolution activity with a rate of 7825.20 µmol h-1 g-1 under visible light irradiation, which is about 93.05 times, 6.38 times and 2.65 times higher than that of 2% C60 /NH2 -MIL-125(Ti), Zn0.5 Cd0.5 S and 45% NH2 -MIL-125(Ti)/Zn0.5 Cd0.5 S, and outperforms the majority of the previously reported MOFs-based photocatalysts. Spectroscopic characterizations and theory calculations indicate that the S-scheme heterojunction can powerfully promote the separation of photogenerated carriers. This work offers a new insight for future design and development of highly active MOFs-based photocatalysts.
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Coronary heart disease and diabetes mellitus are closely related to chronic low-grade inflammation. Interleukin-34 (IL-34) is a new member of the interleukin family discovered in recent years. It is involved in the pathophysiological process of mononuclear phagocyte system mainly via binding to colony stimulating factor-1 receptor, and it is closely related to inflammatory and autoimmune diseases. IL-34 is highly expressed in patients with coronary heart disease or diabetes mellitus. IL-34 induces atherosclerosis and insulin resistance through multiple pro-inflammatory actions, ultimately leading to the occurrence and development of coronary heart disease, type 2 diabetes, and their comorbidities.
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Doença das Coronárias , Diabetes Mellitus Tipo 2 , Resistência à Insulina , Doença das Coronárias/complicações , Diabetes Mellitus Tipo 2/complicações , Humanos , Inflamação/complicações , InterleucinasRESUMO
OBJECTIVES: To investigate the level and significance of serum γ-glutamyl transferase-to-platelet ratio (GPR) and monocyte count to high-density lipoprotein ratio (MHR) in patients with essential hypertension (EH) and unstable angina (UA). METHODS: A total of 218 patients with coronary angiography aged ≥60 years, who were admitted to the EH hospital of the Department of Cardiac Medicine, Affiliated Hospital of Chengde Medical College, were selected from September 2018 to September 2019. They were divided into an EH+UA group (n=113) and an EH group (n=105). In addition, 106 patients with normal coronary angiography who were diagnosed with coronary heart disease were selected as a control group. The general data, blood biochemical indicators, GPR and MHR in each group were compared, and partial correlation analysis and receiver operator characteristic (ROC) curve analysis were performed. RESULTS: Compared with the control group, patients in the EH+UA group and the EH group had higher body mass index (BMI), tyiglyceride (TG), GPR, and MHR, and lower high-density lipoprotein-cholesterol (HDL-C) (all P<0.05); and patients in the EH+UA group had higher white blood cell counts, alanine aminotransferase (ALT), and uric acid (all P<0.05). Compared with the EH group, patients in the EH+UA group had higher GPR and MHR (both P<0.05). Partial correlation analysis showed that after controlling the antihypertensive drugs and lipid-lowering drugs, GPR was found to be positively correlated with BMI, white blood cell count, ALT, TG, and uric acid (r=0.160, 0.111, 0.205, 0.250, 0.154, respectively, all P<0.05), which was negatively correlated with HDL-C (r=-0.238, P<0.05); MHR was positively correlated with BMI, ALT, TG, uric acid, and GPR (r=0.186, 0.307, 0.157, 0.141, 0.223, respectively, all P<0.05), and negatively correlated with HDL-C (r=-0.610, P<0.001). ROC curve analysis showed that GPR had higher specificity and positive predictive value, while MHR had higher sensitivity. When the two indicators were combined, the sensitivity and positive predictive value were higher. CONCLUSIONS: There is a correlation between GPR, MHR and EH combined with UA pectoris, and the combined detection of the two indicators has adjuvant diagnostic value for elderly EH combined with UA.
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Angina Instável , Lipoproteínas HDL , Idoso , HDL-Colesterol , Angiografia Coronária , Hipertensão Essencial , Humanos , MonócitosRESUMO
BACKGROUND: Robot-assisted partial nephrectomy (RAPN) has been widely used worldwide, to determine whether RAPN is a safe and effective alternative to open partial nephrectomy (OPN) via the comparison of RANP and OPN. METHODS: A comprehensive literature search was performed within the databases including PubMed, Cochrane Library, and Embase updated on 30 September 2015. Summary data with their corresponding 95 % confidence intervals (CIs) were calculated using a random effects or fixed effects model. Heterogeneity and publication bias were also evaluated. RESULTS: A total of 16 comparative studies including 3024 cases were used for this meta-analysis. There are no significant differences in the demographic characteristic between the two groups, but the age was lower and the tumor size was smaller for the RAPN group. RAPN had a longer operative time and warm ischemia time but which showed less estimated blood loss, hospital stay, and perioperative complications. No differences existed in the margin status, the change of glomerular filtration rate, transfusion rate, and conversion rate between the two groups. There was no significant publication bias. CONCLUSIONS: RAPN offered a lower rate of perioperative complications, less estimated blood loss, and shorter length of hospital stay than OPN, suggesting that RAPN can be an effective alternative to OPN. Well-designed prospective randomized controlled trials will be helpful in validating our findings.
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Neoplasias Renais/cirurgia , Nefrectomia/métodos , Nefrectomia/estatística & dados numéricos , Procedimentos Cirúrgicos Robóticos/estatística & dados numéricos , Transfusão de Componentes Sanguíneos/estatística & dados numéricos , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Conversão para Cirurgia Aberta/estatística & dados numéricos , Taxa de Filtração Glomerular , Humanos , Tempo de Internação/estatística & dados numéricos , Margens de Excisão , Nefrectomia/normas , Duração da Cirurgia , Resultado do Tratamento , Isquemia Quente/estatística & dados numéricosRESUMO
Considerable amount of high-value transition metals components can be recycled in spent ternary lithium-ion batteries. In this study, we utilized the conductive agent carbon black, obtained from the leaching waste resulting from the chemical recovery of spent lithium-nickel-manganese-cobalt (NCM) oxide cathode materials. This process allows us to create valuable bifunctional catalysts for the oxygen reduction reaction and oxygen evolution reaction (ORR/OER), facilitated by a facile cold plasma activation method, as a part of lithium batteries circular economy. The activated conductive agent (RCA-30) exhibited an ORR half-wave potential of 0.74 V (vs. RHE) in 0.1 mol/L KOH solution, and an OER overpotential of 360 mV at 10 mA cm-2 in 1 mol/L KOH electrolyte, owing to nitrogen doping of carbon black and activation of surface metal oxides. The complete zinc-air batteries incorporating the activated catalysts at the cathode exhibited an open circuit potential of up to 1.48 V and sustained cycling for 100 h at a current density of 5 mA cm-2. Additionally, the activated catalysts contributed to a power density of 92 mW cm-2 and a full discharge capacity of 640 mAh/g.
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Electrochemical CO2 reduction reaction (CO2RR) technology can reduce CO2 emission with converting excess electrical energy to high-value-added chemicals, which however needs further improvement on the electrolyser cell performance. In this work, extensive factors were explored in continuous CO2 electrolysers. Gold, one of the benchmark materials for CO2RR to produce CO, was used as the catalyst. Electrolyser configurations and membrane types have significant influences on cell performance. Compact MEA-constructed gas-phase electrolyser showed better catalytic performance and lower energy consumption. The gas diffusion electrode with a 7:1 mass ratio of total-catalyst-to-polytetrafluoroethylene (PTFE) ionomer exhibited the best performance. At a low total cell voltage of 2.2 V, the partial current density of CO production achieved 196.8 mA cm-2, with 90.6% current efficiency and 60.4% energy efficiency for CO producing respectively. Higher CO selectivity can be achieved using anion exchange membranes, while higher selectivity for hydrogen and formate products can be achieved with cation exchange membranes. This research has pointed out a way on how to improve the CO2RR catalytic performance in flow cells, leaving aside the characteristics of the catalyst itself.
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Graphene and its derivates are extensively applied to enhance the mechanical properties of metal matrix nanocomposites. However, their high reactivity with a metal matrix such as titanium and thus the limited strengthening effects are major problems for achieving high-performance graphene-based nanocomposites. Herein, reduced graphene oxide nanosheets decorated with copper or silver (i.e., Cu@rGO and Ag@rGO) nanopowders are introduced into Ti matrix composites using multiple processes of one-step chemical coreduction, hydrothermal synthesis, low-energy ball milling, spark plasma sintering, and hot rolling. The Cu@rGO/Ti and Ag@rGO/Ti nanocomposites exhibit significantly enhanced strength with superior elongation to fracture (846 MPa-11.6 and 900 MPa-8.4%, respectively, basically reaching the level of the commercial Ti-6Al-4V titanium alloy), which are much higher than those of the fabricated Ti (670 MPa-7.0%) and rGO/Ti composites (726 MPa-11.3%). Furthermore, fracture toughness values of the M@rGO/Ti composites are all significantly improved, that is, the highest KIC value is 34.4 MPa·m1/2 for 0.5Cu@rGO/Ti composites, which is 20.28 and 51.5% higher than those of monolithic Ti and 0.5rGO/Ti composites, respectively. The outstanding mechanical properties of Ag@rGO/Ti and Cu@rGO/Ti composites are attributed to the effective load transfer of in situ formed TiC nanoparticles and the formation of interfacial intermetallic compounds between the rGO nanosheets and Ti matrix. This study provides new insights and approach for the fabrication of metal-modified graphene/Ti composites with a high performance.
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The design and development of high-performance photocatalysts from three aspects of simultaneous enhancement of light harvest, carrier migration rate, and redox reaction rate is still a great challenge. Herein, a novel Co9S8/CdIn2S4 ohmic junction with a robust internal electric field (IEF) is successfully prepared via hydrothermal and in situ synthesis methods and is used for effective photocatalytic H2 evolution (PHE). Under simulated visible light irradiation, the PHE rate of 5% Co9S8/CdIn2S4 can reach 1083.6 µmol h-1 g-1, which is 6.4 times higher than that of CdIn2S4 (170.5 µmol h-1 g-1). The enhanced PHE performance is mainly ascribed to the improved light harvest and carrier separation efficiency and fast surface H2 evolution kinetics. Moreover, Co9S8 nanotubes serve as promising Co-based cocatalysts that can evidently enhance PHE activity. Additionally, Co9S8/CdIn2S4 shows superior stability because the photogenerated carrier transfer path restrains the photocorrosion behavior. The photocatalytic mechanism is proposed based on experimental results and DFT calculations. This work offers new insights for the design and development of highly active photocatalysts from interface engineering.
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Control and insight into the abundance of inter-shelled channel active sites and charge transport mechanism are the long-term challenges for enhancing photocatalytic activity. Herein, the Ni2P quantum dots (QDs) are decorated in the multi-shelled CaTiO3 cube for creating the abundance of inter-shelled channel active sites, which greatly improve the photocatalytic performances for generating H2 and degrading tetracycline (TC) relative to pure CaTiO3 and Ni2P. Moreover, the Z-scheme mechanism and the quantum effect of the Ni2P in multi-shelled CaTiO3 cube play a crucial role for enhancing photocatalytic performance. Furthermore, the photoelectric researches demonstrate that the Ni2P/CaTiO3 heterostructure possesses more abundant active sites, smaller interface transmission resistance and faster photo-generated charge transfer efficiency. This work provides a meaningful model to research other materials with creating the abundance of inter-shelled channel active sites for the photo-electrocatalytic field.
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Plants requiring an insect pollinator often produce nectar as a reward for the pollinator's visitations. This rich secretion needs mechanisms to inhibit microbial growth. In Nicotiana spp. nectar, anti-microbial activity is due to the production of hydrogen peroxide. In a close relative, Petunia hybrida, limited production of hydrogen peroxide was found; yet petunia nectar still has anti-bacterial properties, suggesting that a different mechanism may exist for this inhibition. The nectar proteins of petunia plants were compared with those of ornamental tobacco and significant differences were found in protein profiles and function between these two closely related species. Among those proteins, RNase activities unique to petunia nectar were identified. The genes corresponding to four RNase T2 proteins from Petunia hybrida that show unique expression patterns in different plant tissues were cloned. Two of these enzymes, RNase Phy3 and RNase Phy4 are unique among the T2 family and contain characteristics similar to both S- and S-like RNases. Analysis of amino acid patterns suggest that these proteins are an intermediate between S- and S-like RNases, and support the hypothesis that S-RNases evolved from defence RNases expressed in floral parts. This is the first report of RNase activities in nectar.
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Petunia/enzimologia , Néctar de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Ribonucleases/metabolismo , Sequência de Aminoácidos , Dados de Sequência Molecular , Petunia/química , Petunia/classificação , Petunia/genética , Filogenia , Néctar de Plantas/química , Néctar de Plantas/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Ribonucleases/química , Ribonucleases/genética , Alinhamento de SequênciaRESUMO
A Typha Angustifolia-like MoS2/carbon nanofiber composite as both a chemically trapping agent and redox conversion catalyst for lithium polysulfides has been successfully synthesized via a simple hydrothermal method. Cycling performance and coulombic efficiency have been improved significantly by applying the Typha Angustifolia-like MoS2/carbon nanofiber as the interlayer of a pure sulfur cathode, resulting in a capacity degradation of only 0.09% per cycle and a coulombic efficiency which can reach as high as 99%.
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Cu, Co and Zn modified N-doped porous carbons (CuCo/Zn@NPC) are prepared using a polymetallic homogeneous doping and self-templating method as high performance non-noble metal catalysts for the hydrogenation of furfural (FF) to furfuryl alcohol (FAL). The CuCo/Zn@NPC-600 catalyst after treatment at 600 °C shows a superior catalytic activity with nearly 100% conversion of FF and an almost 100% selectivity of FAL using H2 at 140 °C. Meanwhile in the catalytic transfer hydrogenation (CTH) using 2-propanol as a H-donor, the conversion of FF reaches 95.8% and the selectivity of FAL is 99.1%. The results show that the Zn dopant leads to 37.3 times higher yield on the CuCo/Zn@NPC-600 catalyst than that on CuCo@NPC-600, and 2.3 times higher than that on Co/Zn@NPC-600 with Cu dopants. The efficient activity of the CuCo/Zn@NPC-600 catalyst is mainly due to the highly dispersed metal nanoparticles, the advanced porous structure resulting from Zn escape from the precursor template, and the synergistic effect between Cu and Co. Furthermore, the CuCo/Zn@NPC-600 catalyst exhibits good recyclability in FF hydrogenation in four cycle tests. The advanced synthesis method using a homogeneous doping and self-templating strategy sheds light on preparing effective catalysts for hydrogenation of biomass-based compounds.
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Intelligent human-machine interfaces (HMIs) integrated wearable electronics are essential to promote the Internet of Things (IoT). Herein, a curcumin-assisted electroless deposition technology is developed for the first time to achieve stretchable strain sensing yarns (SSSYs) with high conductivity (0.2 Ω cm-1) and ultralight weight (1.5 mg cm-1). The isotropically deposited structural yarns can bear high uniaxial elongation (>>1100%) and still retain low resistivity after 5000 continuous stretching-releasing cycles under 50% strain. Apart from the high flexibility enabled by helical loaded structure, a precise strain sensing function can be facilitated under external forces with metal-coated conductive layers. Based on the mechanics analysis, the strain sensing responses are scaled with the dependences on structural variables and show good agreements with the experimental results. The application of interfacial enhanced yarns as wearable logic HMIs to remotely control the robotic hand and manipulate the color switching of light on the basis of gesture recognition is demonstrated. It is hoped that the SSSYs strategy can shed an extra light in future HMIs development and incoming IoT and artificial intelligence technologies.
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Protecting an anode from deterioration during charging/discharging has been seen as one of the key strategies in achieving high-performance lithium (Li)-O2 batteries and other Li-metal batteries with a high energy density. Here, we describe a facile approach to prevent the Li anode from dendritic growth and chemical corrosion by constructing a SiO2/GO hybrid thin layer on the surface. The uniform pore-preserving layer can conduct Li ions in the stripping/plating process, leading to an effective alleviation of the dendritic growth of Li by guiding the ion flux through the microstructure. Such a preservation technique significantly enhances the cell performance by enabling the Li-O2 cell to cycle up to 348 times at 1 A·g-1 with a capacity of 1000 mA·h·g-1, which is several times the cycles of cells with pristine Li (58 cycles), Li-GO (166 cycles), and Li-SiO2 (187 cycles). Moreover, the rate performance is improved, and the ultimate capacity of the cell is dramatically increased from 5400 to 25,200 mA·h·g-1. This facile technology is robust and conforms to the Li surface, which demonstrates its potential applications in developing future high-performance and long lifespan Li batteries in a cost-effective fashion.
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The metal-support interaction offers electronic, compositional, and geometric effects that could enhance catalytic activity and stability. Herein, a high corrosion resistance and an excellent electrical conductivity MXene (Ti3C2Tx) hybrid with a carbon nanotube (CNT) composite material is developed as a support for Pt. Such a composite catalyst enhances durability and improved oxygen reduction reaction activity compared to the commercial Pt/C catalyst. The mass activity of Pt/CNT-MXene demonstrates a 3.4-fold improvement over that of Pt/C. The electrochemical surface area of Pt/CNT-Ti3C2Tx (1:1) catalysts shows only 6% drop with respect to that in Pt/C of 27% after 2000 cycle potential sweeping. Furthermore, the Pt/CNT-Ti3C2Tx (1:1) is used as a cathode catalyst for single cell and stack, and the maximum power density of the stack reaches 138 W. The structure distortion of the Pt cluster induced by MXene is disadvantageous to the desorption of O atoms. This issue can be solved by adding CNT on MXene to stabilize the Pt cluster. These remarkable catalytic performances could be attributed to the synergistic effect between Pt and CNT-Ti3C2Tx.
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Interfacial interactions within a multi-phase polymer solution play critical roles in processing control and mass transportation in chemical engineering. However, the understandings of these roles remain unexplored due to the complexity of the system. In this study, we used an efficient analytical method-a nonequilibrium molecular dynamics (NEMD) simulation-to unveil the molecular interactions and rheology of a multiphase solution containing cetyltrimethyl ammonium chloride (CTAC), polyacrylamide (PAM), and sodium salicylate (NaSal). The associated macroscopic rheological characteristics and shear viscosity of the polymer/surfactant solution were investigated, where the computational results agreed well with the experimental data. The relation between the characteristic time and shear rate was consistent with the power law. By simulating the shear viscosity of the polymer/surfactant solution, we found that the phase transition of micelles within the mixture led to a non-monotonic increase in the viscosity of the mixed solution with the increase in concentration of CTAC or PAM. We expect this optimized molecular dynamic approach to advance the current understanding on chemical-physical interactions within polymer/surfactant mixtures at the molecular level and enable emerging engineering solutions.
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Antibiotic pollution in tap water, surface water, and effluent needs to be controlled in China. Adsorption is an economical and eco-friendly way to solve the antibiotic contamination problem, such as tylosin. In this study, the chitosan/cellulose nanocomposite adsorbents entrapped with activated carbon are prepared by a sol-gel phase inversion method. Structures and properties of the adsorbents are characterized by SEM, EDXS, BET, XRD, FTIR XPS and Zeta potentials. The adsorption behavior of CCM-AC on tylosin is determined by batch and fixed-bed adsorption experiments, while their adsorption mechanism is also studied. The maximum adsorption capacity is 59.26 mg g-1, while the adsorption behavior is in accordance with the Langmuir equation and pseudo-second-order kinetics. These results confirm that the tylosin adsorption process is affected by chemical and physical interactions, and the adsorbent can be captured by tylosin with H-bond, electrostatic and π-π electron-donor-acceptor interaction. Adsorption experiments are significantly affected by pH.
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Precursor-reforming strategy induced graphitic carbon nitride (g-C3N4) with different morphologies for enhanced photocatalytic hydrogen (H2) evolution activity is highly desirable. Herein, g-C3N4 microtubes (mg-C3N4) with adjustable closure degree of microtube orifice and spatial anisotropic charge separation are established by conquering hydrogen bond during thermally exfoliate precursor. Compared to the bulk g-C3N4 (bg-C3N4) and ultrathin g-C3N4 (ug-C3N4), the tubular structure endows mg-C3N4 with spatial anisotropic charge separation that accelerates transfer of charge carriers. As expected, the photocatalytic H2 evolution (PHE) activity of mg-C3N4 has been obviously enhanced. Particularly, the mg-C3N4-24 shows the best PHE activity (957.9⯵molâ¯h-1â¯g-1), which is over 18.72 and 3.77 times higher than the bg-C3N4 and ug-C3N4, respectively. In addition, selective photo-deposition experiment results reveal a charge carriers migration behavior that photoproduction electrons migrate to the outer shell and holes prefer to move onto the inner shell of mg-C3N4, thus achieving efficient spatial anisotropic charge separation. We firmly believe that the work presents significant advancement for the design of other materials by precursor-reforming strategy.
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CuCo2S4 is regarded as a promising electrode material for supercapacitor, but has inferior conductivity and poor cyclic stability which restrict its wide-range applications. In this work, hierarchically hybrid composite of CuCo2S4/carbon nanotubes (CNTs) was synthesized using a facile hydrothermal and sulfuration process. The embedded CNTs in the CuCo2S4 matrix provided numerous effective paths for electron transfer and ion diffusion, and thus promoted the faradaic reactions of the CuCo2S4 electrode in the energy storage processes. The CuCo2S4/CNTs-3.2% electrode exhibited a significantly increased specific capacitance of 557.5 F g-1 compared with those of the pristine CuCo2S4 electrode (373.4 F g-1) and CuO/Co3O4/CNTs-3.2% electrode (356.5 F g-1) at a current density of 1 A g-1. An asymmetric supercapacitor (ASC) was assembled using the CuCo2S4/CNTs-3.2% as the positive electrode and the active carbon as the negative electrode, which exhibited an energy density of 23.2 Wh kg-1 at a power density of 402.7â¯Wâ¯kg-1. Moreover, the residual specific capacitance of this ASC device retained 85.7% of its original value after tested for 10,000 cycles, indicating its excellent cycle stability.