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In order to increase the working voltage of the aqueous zinc ion batteries with manganese-based material as the positive electrode material, an ultrathin nanosheet array (MnCO3 NA) was grown on a nickel foam substrate by a one-step solvothermal method. The structure, morphology and electrochemical properties of MnCO3 NA were characterized by X-ray diffraction (XRD), scanning electron microscope, transmission electron microscope and battery performance tester. The experiments results showed that the thickness of the MnCO3 NA was about 30 nm and the height was about 500 nm. It was directly applied to the zinc ion battery in the alkaline electrolyte, delivering a high working voltage of 1. 73 V, a specific discharge capacity of 255. 41 mAh/g at 0. 1 A/g, and a capacity retention of 83. 1% after 270 charge-discharge cycles at 0. 5 A/g. In addition, the zinc storage mechanism of the electrode was a mono-phase reaction from Mn2+ to Mn3+, which was analyzed by ex-situ XRD and photoelectron spectroscopy at different potential states. [ABSTRACT FROM AUTHOR]

Intercalation chemistry/engineering has been widely investigated in the development of electrochemical energy storage. Graphite, as an old intercalation host, is receiving vigorous attention again via a new halogen intercalation. Whereas, exploiting new intercalation hosts and optimizing the intercalation effect still remains a great challenge. This study fabricates a Cu2Se intercalation compound showing expanded interlayer space and nanosheet array features by using a green growth approach, in which cetyltrimethyl ammonium bromide (CTAB) is inserted into Cu2Se at an ambient temperature. When acting as an electrode material for sodium‐ion batteries, the Cu2Se–CTAB nanosheet arrays exhibit excellent discharge capacity and rate capability (426.0 mAh g−1 at 0.1 A g−1 and 238.1 mAh g−1 at 30 A g−1), as well as high capacity retention of ≈90% at 20 A g−1 after 6500 cycles. Benefiting from the porous array architecture, the transport of electrolytes is facilitated on the surface of Cu2Se nanosheets. In particular, the CTAB intercalated in the interlayer space of Cu2Se can increase its buffer space, stabilize the polyselenide shuttle, and prevent the fast growth of Cu nanoparticles during its electrochemical process. [ABSTRACT FROM AUTHOR]

Abstract: Layered transition metal sulfides (LTMSs) have tremendous commercial potential in anode materials for sodium‐ion batteries (SIBs) in large‐scale energy storage application. However, it is a great challenge for most LTMS electrodes to have long cycling life and high‐rate capability due to their larger volume expansion and the formation of soluble polysulfide intermediates caused by the conversion reaction. Herein, layered CuS microspheres with tunable interlayer space and pore volumes are reported through a cost‐effective interaction method using a cationic surfactant of cetyltrimethyl ammonium bromide (CTAB). The CuS–CTAB microsphere as an anode for SIBs reveals a high reversible capacity of 684.6 mAh g−1 at 0.1 A g−1, and 312.5 mAh g−1 at 10 A g−1 after 1000 cycles with high capacity retention of 90.6%. The excellent electrochemical performance is attributed to the unique structure of this material, and a high pseudocapacitive contribution ensures its high‐rate performance. Moreover, in situ X‐ray diffraction is applied to investigate their sodium storage mechanism. It is found that the long chain CTAB in the CuS provides buffer space, traps polysulfides, and restrains the further growth of Cu particles during the conversion reaction process that ensure the long cycling stability and high reversibility of the electrode material. [ABSTRACT FROM AUTHOR]