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Considering the connected function, high conductivity and electrochemical double layer capacitance properties of reduced graphene oxide (RGO), the NiMoS 4 nanosheets were anchored on RGO coated Ni foam by a facile hydrothermal method to obtain the NiMoS 4 @RGO/Ni foam self-supporting electrode without the extra binders. Surprisingly, the prepared NiMoS 4 @RGO/Ni foam with unique hierarchical lamellar structure can exhibit the high specific capacity of 408 mAh/g at 0.5 A/g, which can be compared with all relevant NiMoS 4 reports. In view of the good supercapacitor performances and practical application feasibility of NiMoS 4 @RGO/Ni foam, the NiMoS 4 @RGO/Ni foam//AC hybrid supercapacitor device also can show the comparable energy density of 67.4 Wh/kg at 562.5 W/kg to that of all NiMoS 4 based hybrid supercapacitors, as well as the good cycle stability. This work can indeed improve the supercapcaitor properties of NiMoS 4 based materials, and be also treated as an important attempt of NiMoS 4 based materials for supercapacitors. Unlabelled Image • The connected NiMoS 4 nanosheets and Ni foam was bonded by RGO. • The NiMoS 4 @RGO/Ni foam can serve as a self-supporting electrode. • The NiMoS 4 @RGO/Ni foam exhibits the ultrahigh specific capacity of 408 mAh/g. • The NiMoS 4 @RGO/Ni foam//AC device shows comparable energy density of 67.4 Wh/kg. [ABSTRACT FROM AUTHOR]

The sponge-like NiMoS 4 nanosheets were in-situ induced/grown on self-supported Ni foam, which can be directly applied as supercapacitor electrode without tedious preparation process and charge transfer limited binders. The obtained NiMoS 4 /Ni foam electrode can exhibit the high specific capacity of 233 mA h/g at 0.75 A/g, owing to the uniform three-dimensional sponge-like network shape with favorable electrons/ions transfer channels. In addition, the assembled NiMoS 4 /Ni foam//AC asymmetric supercapacitor can possess the energy density of 32 Wh/kg and good stability of 84 % capacity retention after 8000 cycles. This work cannot only provide a new preparation method of NiMoS 4 on Ni foam without introducing nickel sulfides, but also exhibits the high-performance NiMoS 4 /Ni foam supercapacitor electrode. [ABSTRACT FROM AUTHOR]

Nanosheet-constructed porous CoMoS 4 arrays are grown on 3D self-supported Ni foam by a simple solvothermal strategy. The resulting sample can be immediately served as an adhesive-free electrode of supercapacitors. Surprisingly, the obtained CoMoS 4 /Ni foam with high chemical activity and unique structure exhibits excellent performance including the high specific capacity of 276 mAh/g at 0.25 A/g. Moreover, the prepared CoMoS 4 /Ni foam and commercial activated carbon (AC) are specified as the positive/negative electrodes of a hybrid supercapacitor. The assembled CoMoS 4 /Ni foam//AC hybrid device outputs a high specific energy of 58 Wh/kg at a specific power of 328 W/kg, and 95% of initial capacity after 10,000 charge-discharge cycles. These conditions are favorable for the practical application of the prepared CoMoS 4 /Ni foam. Therefore, the nanosheet-constructed porous CoMoS 4 arrays on Ni foam can be considered as a hopeful electrode for energy storage devices. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) and conjugated microporous polymers (CMPs) have become candidates with potential for electrochemical energy-related applications which because of the characteristic of adjustable architecture, physicalchemical stability, simple manufacture and feasible functionalization. [Display omitted] • COFs and CMPs have attracted widespread attention as electrode materials in electrochemical energy storage and conversion. • This review provides a detailed classification of COFs and CMPs as electrode materials from the perspective of design principles. • This review summarizes the latest progress of COFs and CMPs as electrode materials in lithium - ion batteries, supercapacitors and electrochemical water - splitting. • The advantages and the challenges of COFs and CMPs in electrochemical energy storage and conversion are described. Covalent organic framework (COFs) and conjugated microporous polymers (CMPs) adopt rigid structure directing motifs as building blocks, which are connected by covalent bonds in a specific polymerization reaction with crystalline and amorphous morphology, respectively. They usually possess high specific surface area, controllable porous structure, as well as physical and chemical stability. Due to the diversity of organic monomers and organic reactions, COFs and CMPs can be synthesized by designing suitable monomers and organic polymerization reactions for specific applications. In recent years, COFs and CMPs as functional materials have received extensive attention, and great progress have been made in electrochemical energy storage and conversion. In this review, we systematically sorted out the design principles of COFs and CMPs as lithium-ion batteries (LIBs) and supercapacitors (SC) electrode materials, as well as water-splitting electrocatalysts. Subsequently, the latest advances in COFs and CMPs for energy storage and conversion systems were introduced from the perspective of synthesis strategies. Finally, we put forward the outlook and prospects of COFs and CMPs for LIBs, supercapacitors, hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) with high-efficiency. [ABSTRACT FROM AUTHOR]

Summary: The CoMoO4 microspheres constructed from ultrathin nanosheets were synthesized by means of a simple chemical precipitation using urotropin (C6H12N4) as a soft template, which were used as the electrode materials for supercapacitors. It was found that the CoMoO4 sample with 3 mmol of added urotropin (vs 1 mmol CoCl2) exhibits the uppermost specific capacity value of 89 mAh/g at a current density of 0.25 A/g due to its unique mesoporous structure and large specific surface area. In addition, a hybrid supercapacitor was established by the CoMoO4 microspheres (positive electrode) and activated carbon (AC, negative electrode). The obtained CoMoO4//AC hybrid supercapacitor possesses a specific energy value of 34 Wh/kg at 375 W/kg. Most importantly, this device owns excellent cycle stability with no capacity decay observed after 10 000 cycles. These good electrochemical properties of CoMoO4 microspheres are promising in the practical use fields. [ABSTRACT FROM AUTHOR]