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[Display omitted] • Amorphous/crystalline H-NiMoS 4 /NiS 2 hollow sphere was successfully constructed. • A high specific capacitance and good cycling performance was obtained. • The capacity retention of HSC was 83.7% after 20,000 cycles. • The HSC displayed a high energy density of 38.6 Wh kg−1 at 958.6 W kg−1. Phase engineering offers a promising strategy to tailor the physiochemical properties to further improve their electrochemical performance toward energy storage. However, it remains a challenge to fabricate well-defined amorphous/crystalline hetero-phase metal sulfides with high-density heterointerfaces. Herein, the synthesis of hetero-phase combination of amorphous NiMoS 4 and crystalline NiS 2 that possesses hollow nanosphere structure decorated by nanosheets (named as H-NiMoS 4 /NiS 2) is reported. Benefiting from the construction of the hollow nanosphere coated by nanosheets, amorphous/crystalline hetero-phase junction, and strong Ni-S hybridization, H-NiMoS 4 /NiS 2 electrode exhibits high specific capacity, outstanding rate capability and excellent cycling stability. Moreover, an all-solid-state supercapacitor was assembled with H-NiMoS 4 /NiS 2 as cathode and needle coke oxide (NCO) as anode, which can achieve remarkably high energy density of 38.6 Wh kg−1 at a power density of 958.6 W kg−1 and outstanding capacity retention of 83.7% after 20,000 cycling. The preparation of novel H-NiMoS 4 /NiS 2 nanomaterial with a hetero-phase of amorphous and crystalline provides a new solution for improving the structural stability and capacitor storage performance as electrodes for supercapacitors. [ABSTRACT FROM AUTHOR]

• The hierarchical M-ZCOH/NPG/NF heterostructures were successfully constructed. • The BIEF in the heterointerface enhanced electronic/ionic transport dynamics. • A high capacity reaching ∼1247.1C g−1 (∼2771.3 F g−1) at 1 A g−1 was obtained. • The HSC displayed ultrahigh energy density of ∼78.3 Wh kg−1 at ∼800 W kg−1. The superior electronic/ionic transport dynamics of electrode materials have been crucial to achieve appealing high performance for supercapacitors. Herein, a fascinating one-dimensional (1D) zinc cobalt hydroxide nanobelts/0D irregular manganese dioxide nanoparticles (M-ZCOH) have been vertically loaded into the 3D Ni foam (NF) substrate wrapped by nitrogen-doped graphene (NPG) (M-ZCOH/NPG/NF) for supercapacitors. The ingeniously designed M-ZCOH/NPG/NF composites feature powerful built-in electric field (BIEF) introduced by well-defined heterointerface with abundant oxygen vacancies defects. The formed electron accumulation triggering strong interfacial interaction verified by the differential charge density analysis may endow M-ZCOH/NPG/NF with the extra driving force to increase the diffusion/adsorption of electrolyte ions, thereby facilitating electron/ion transfer kinetics. Also, the qualitative negative shift of the d band center for M-ZCOH composites further evidences a lower electron/ion transfer barrier compared with the monomers. Obviously, the penetrating understanding of heterointerface on the improved properties is manifestly interpreted by combining theoretical and experimental analysis. Moreover, the ingenious strategy of engineering the heterointerfaces in unique heterostructure with rich defects may provide a new prospect for optimizing other advanced materials in sustainable energy storage systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • A nitrilotriacetic acid-assisted strategy for controllable synthesis of NiS/carbon hexahedrons was proposed. • Synchronous realization of the combination of carbon with NiS and morphology controlled in one step. • Formation mechanism and determinants of NiS/carbon composites are revealed. • Enhanced power density (4187.2 W kg−1) and energy density (30.8 Wh kg−1). Effective adjustment of structure and morphology is considered to be an available strategy to improve the energy storage performance of supercapacitor electrode materials. Herein, a series of hierarchical NiS/carbon hexahedrons consist of self-assembling nanoplates or nanorods were synthesized via nitrilotriacetic acid (NTA)-assisted hydrothermal strategy. This study demonstrates that the micro-morphology of the unit structure constituting the hexahedrons can be controlled by adjusting the concentration of NTA. Benefiting from synergetic effect of high void space, hierarchical assembly mode and integrated composite structure, NiS/carbon hexahedrons promote adequate exposure of abundant active sites and enhance the structural stability, donating superior energy storage performance. As expected, the optimized NiS/carbon electrode (NiS/NTA-2) exhibits superb capacitive performance, including excellent specific capacitance of 1530.4 F g−1 at 1.0 A g−1 and remarkable cycle stability with 85.6% after 5000 cycles. Employing the as-prepared NiS/NTA-2 composites as positive electrode, the hybrid supercapacitor device with spectacular capacity of maximum energy density and power density up to 35.1 Wh kg−1 and 4509.3 W kg−1 and impressive long-term stability of 87.2% retention after 5000 cycles is assembled. Moreover, a light-emitting diode (LED) is successfully illuminated for up to 12 min by two devices connected in series. Based on this strategy, high-performance energy storage devices can be further developed through utilizing the modulation effect of metal complexes to design morphology controlled electrode materials. [ABSTRACT FROM AUTHOR]