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It is a great challenge to achieve both high specific capacity and high energy density of supercapacitors by designing and constructing hybrid electrode materials through a simple but effective process. In this paper, we proposed a hierarchically nanostructured hybrid material combining Zn 0.76 Co 0.24 S (ZCS) nanoparticles and Co(OH) 2 (CH) nanosheets using a two-step hydrothermal synthesis strategy. Synergistic effects between ZCS nanoparticles and CH nanosheets result in efficient ion transports during the charge-discharge process, thus achieving a good electrochemical performance of the supercapacitor. The synthesized ZCS@CH hybrid exhibits a high specific capacity of 1152.0 C g -1 at a current density of 0.5 A g -1 in 2 M KOH electrolyte. Its capacity retention rate is maintained at ∼ 70.0% when the current density is changed from 1 A g -1 to 10 A g -1 . A hybrid supercapacitor (HSC) assembled from ZCS@CH as the cathode and active carbon (AC) as the anode displays a capacitance of 155.7 F g -1 at 0.5 A g -1 , with a remarkable cycling stability of 91.3% after 12,000cycles. Meanwhile, this HSC shows a high energy density of 62.5 Wh kg -1 at a power density of 425.0 W kg -1 , proving that the developed ZCS@CH is a promising electrode material for energy storage applications., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

MnCo 2 O 4 is regarded as a good electrode material for supercapacitor due to its high specific capacity and good structural stability. However, its poor electrical conductivity limits its wide-range applications. To solve this issue, we integrated the MnCo 2 O 4 with Ni 3 S 4 , which has a good electrical conductivity, and synthesized a MnCo 2 O 4 /Ni 3 S 4 nanocomposite using a two-step hydrothermal process. Comparing with individual MnCo 2 O 4 and Ni 3 S 4 , the MnCo 2 O 4 /Ni 3 S 4 nanocomposite showed a higher specific capacity and a better cycling stability as the electrode for the supercapacitor. The specific capacity value of the MnCo 2 O 4 /Ni 3 S 4 electrode was 904.7 C g -1 at 1 A g -1 with a potential window of 0-0.55 V. A hybrid supercapacitor (HSC), assembled using MnCo 2 O 4 /Ni 3 S 4 and active carbon as the cathode and anode, respectively, showed a capacitance of 116.4 F g -1 at 1 A g -1 , and a high energy density of 50.7 Wh kg -1 at 405.8 W kg -1 . Long-term electrochemical stability tests showed an obvious increase of the HSC's capacitance after 5500 charge/discharge cycles, reached a maximum value of ∼162.7% of its initial value after 25,000 cycles, and then remained a stable value up to 64,000 cycles. Simultaneously, its energy density was increased to 54.2 Wh kg -1 at 380.3 W kg -1 after 64,000 cycles., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

CuCo 2 S 4 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 CuCo 2 S 4 /carbon nanotubes (CNTs) was synthesized using a facile hydrothermal and sulfuration process. The embedded CNTs in the CuCo 2 S 4 matrix provided numerous effective paths for electron transfer and ion diffusion, and thus promoted the faradaic reactions of the CuCo 2 S 4 electrode in the energy storage processes. The CuCo 2 S 4 /CNTs-3.2% electrode exhibited a significantly increased specific capacitance of 557.5 F g -1 compared with those of the pristine CuCo 2 S 4 electrode (373.4 F g -1 ) and CuO/Co 3 O 4 /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 CuCo 2 S 4 /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 402.7 W 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., (Copyright © 2019 Elsevier Inc. All rights reserved.)