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Metal zinc (Zn) is being explored as a possible anode for aqueous zinc ion batteries (AZIBs). However, unrestrained Zn dendrite caused by “tip effect” and chemical corrosion continue to plague the Zn deposition process, limiting the functionality of AZIBs and prohibiting their use at high current densities. This work presents an in situ approach for introducing homogeneous ZnO nanoarrays onto the surface of Zn foil (Zn@ZnO NAs) as a functional protective interphase. On the one hand, well‐distributed ZnO NAs protection layer can regulate the “tip effect” and confine the growth of Zn dendrite. On the other hand, the ZnO NAs layer can enhance the desolvation and diffusion process of Zn2+ on the surface of anode, attributing to low voltage hysteresis and exceptional electrochemical performance at high current densities. As a result, the Zn@ZnO NAs exhibits a low voltage hysteresis of 50.8 mV with a superb lifespan of 1200 h at a current density of 5 mA cm−2. Moreover, Zn@ZnO NAs||α‐MnO2 full‐cell shows a superior cycling performance after 500 cycles at 0.5 A g−1 with a capacity of 216.69 mAh g−1. This work is expected to provide ideas for designing other reversible zinc anode chemical systems, especially under a high current density. [ABSTRACT FROM AUTHOR]

Sn-based materials are considered as a prospective anode for lithium-ion batteries because of their high theoretical lithium storage capacity and large reserves. But the application of Sn-based materials is still hampered by their significant capacity decay owing to volume changes during lithiation and delithiation. To address this problem, we propose the in-situ synthesis of amorphous carbon-coated (thickness: ∼3 nm) Sn–SnO 2 nanoparticles (size: ∼20–50 nm) embedded in helical carbon nanotubes (diameter: ∼30 nm) grown on Cu foam (C@Sn–SnO 2 /CNT) via hydrothermal and subsequent chemical vapor deposition process. The 3D hierarchical framework decorated by C@Sn–SnO 2 nanoparticles provides enhanced contact between the electrode and electrolyte, and guarantees an efficient reversible conversion reaction. Moreover, the introduction of the carbon layer and carbon nanotubes inhibits large volume changes of Sn and SnO 2 during cycling. In comparison with pure SnO 2 , C@Sn–SnO 2 /CNT displays superior lithium storage capability, rate performance, and cycle stability. The discharge capacity for C@Sn–SnO 2 /CNT at 0.2 A g−1 is 1772 mAh g−1 in the first cycle and 856 mAh g−1 after 300 cycles, as well as 480 mAh g−1 at 1 A g−1. Consequently, C@Sn–SnO 2 /CNT possesses enormous potentiality for practical application in high-performance lithium-ion batteries. [Display omitted] • C@Sn–SnO 2 /CNTs has been in-situ synthesized on Cu foam. • Sn–SnO 2 composites exhibit superior lithium storage capacity and reversibility. • C@Sn–SnO 2 /CNTs possessed hierarchical and interconnected structures. • C@Sn–SnO 2 /CNTs showed enhanced electrochemical performance and cycling stability. [ABSTRACT FROM AUTHOR]

Co‐free O3‐type NaNi0.5Mn0.5O2 cathode material for sodium‐ion batteries has shown great promise due to its high theoretical capacity and plentiful Na reservoir. However, the rapid capacity recession caused by harmful phase transition and large volume strain severely restricts their practical application. Herein, the obstacle is well addressed by constructing a P2&O3 biphasic structure via a customized boron‐doping strategy. The light‐weight boron doping in the interstitial position reduces the energy gap of the formation energy of P2 and O3 structure, which induces the formation of P2&O3 biphase in high Na state. In addition, the biphasic structure exhibits near zero volume strain due to the lattice interlocking effect of P2&O3, as identified by in situ X‐ray diffraction measurement. As a result, it presents a remarkable cyclability with a capacity retention of 85.2% over 1000 cycles at a high rate of 5 C. More importantly, a pouch‐type full‐cell device can exhibit a long cycling life with 70.8% capacity retention over 150 cycles at 0.1 C. This work can offer a new inspiration for designing advanced high sodium electrode materials via light element doping for future energy storage devices. [ABSTRACT FROM AUTHOR]

Sodium iron phosphate (NaFePO4) has attracted significant attention because of its high theoretical capacity (155 mA h g−1), remarkable structural stability, and abundant elemental composition. However, the electrochemical reversibility of maricite NaFePO4 is generally considered inactive. Herein, a nanoengineering strategy to activate the electrochemical activity of maricite NaFePO4 is presented. This approach involves the construction of ultrasmall maricite NaFePO4 nanoparticles encapsulated within an ultrathin carbon layer (denoted as m‐NFP@C), which greatly improves the electrochemical properties of the material. Notably, the optimized m‐NFP@C nanoparticles exhibit an impressive reversible capacity of 101.4 mA h g−1 after 100 cycles at a current density of 20 mA g−1, demonstrating a remarkable capacity retention of 90.5%. Furthermore, when coupled with the bismuth–carbon microfoam‐like compound (Bi@NC‐MF) anode, the fabricated sodium‐ion full cell exhibits exceptional cycling stability with a capacity retention of 90.6% over 250 cycles. The remarkable electrochemical performance of this material can be attributed to its excellent structural stability, ultrafine nanostructure, and uniform carbon coating, which effectively shorten the Na+ diffusion pathways, prevent the aggregation and fragmentation of nanoparticles, and enhance electronic conductivity. This work is anticipated to open up a new route for activating maricite NaFePO4 and advancing the development of polyanion‐type electrode materials. [ABSTRACT FROM AUTHOR]