The high performance of a pseudocapacitor electrode relies largely on a scrupulous design of nanoarchitectures and smart hybridization of bespoke active materials. We present a powerful two-step solution-based method for the fabrication of transition metal oxide core/shell nanostructure arrays on various conductive substrates. Demonstrated examples include Co(3)O(4) or ZnO nanowire core and NiO nanoflake shells with a hierarchical and porous morphology. The "oriented attachment" and "self-assembly" crystal growth mechanisms are proposed to explain the formation of the NiO nanoflake shell. Supercapacitor electrodes based on the Co(3)O(4)/NiO nanowire arrays on 3D macroporous nickel foam are thoroughly characterized. The electrodes exhibit a high specific capacitance of 853 F/g at 2 A/g after 6000 cycles and an excellent cycling stability, owing to the unique porous core/shell nanowire array architecture, and a rational combination of two electrochemically active materials. Our growth approach offers a new technique for the design and synthesis of transition metal oxide or hydroxide hierarchical nanoarrays that are promising for electrochemical energy storage, catalysis, and gas sensing applications.

The review presents an overview of the recent advances in inorganic solid lithium ion conductors, which are of great interest as solid electrolytes in all-solid-state lithium batteries. It is focused on two major categories: crystalline electrolytes and glass-based electrolytes. Important systems such as thio-LISICON Li 10 SnP 2 S 12 , garnet Li 7 La 3 Zr 2 O 12 , perovskite Li 3x La (2/3) x TiO 3 , NASICON Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 , and glass-ceramic xLi 2 S·(1 − x )P − 2 S 5 and their progress are described in great detail. Meanwhile, the review discusses different ongoing strategies on enhancing conductivity, optimizing electrolyte/electrode interface, and improving cell performance.

We report the preparation of a nickel-foam-supported graphene sheet/porous NiO hybrid film by the combination of electrophoretic deposition and chemical-bath deposition. The obtained graphene-sheet film of about 19 layers was used as the nanoscale substrate for the formation of a highly porous NiO film made up of interconnected NiO flakes with a thickness of 10-20 nm. The graphene sheet/porous NiO hybrid film exhibits excellent pseudocapacitive behavior with pseudocapacitances of 400 and 324 F g(-1) at 2 and 40 A g(-1), respectively, which is higher than those of the porous NiO film (279 and 188 F g(-1) at 2 and 40 A g(-1)). The enhancement of the pseudocapacitive properties is due to reinforcement of the electrochemical activity of the graphene-sheet film.

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Exploration of high‐performance cathode materials for rechargeable aqueous Zn ion batteries (ZIBs) is highly desirable. The potential of molybdenum trioxide (MoO 3 ) in other electrochemical energy storage devices has been revealed but held understudied in ZIBs. Herein, a demonstration of orthorhombic MoO 3 as an ultrahigh‐capacity cathode material in ZIBs is presented. The energy storage mechanism of the MoO 3 nanowires based on Zn 2+ intercalation/deintercalation and its electrochemical instability mechanism are particularly investigated and elucidated. The severe capacity decay of the MoO 3 nanowires during charging/discharging cycles arises from the dissolution and the structural collapse of MoO 3 in aqueous electrolyte. To this end, an effective strategy to stabilize MoO 3 nanowires by using a quasi‐solid‐state poly(vinyl alcohol)(PVA)/ZnCl 2 gel electrolyte to replace the aqueous electrolyte is developed. The capacity retention of the assembled ZIBs after 400 charge/discharge cycles at 6.0 A g −1 is significantly boosted, from 27.1% (in aqueous electrolyte) to 70.4% (in gel electrolyte). More remarkably, the stabilized quasi‐solid‐state ZIBs achieve an attracting areal capacity of 2.65 mAh cm −2 and a gravimetric capacity of 241.3 mAh g −1 at 0.4 A g −1 , outperforming most of recently reported ZIBs.