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Organic batteries with improved electrode wettability will exhibit a better electrochemical performance. How about the relationship between electrode wettability and battery performance in aqueous batteries? Here the effect of cathode wettability in aqueous zinc-ion batteries (AZIBs) on the zinc-ion diffusion and charge transfer based on a research platform of cellulose nanowhiskers (CNWs)/graphene/MnO2 wire-in-scroll nanowires with water contact angles turning from 64.70 ​± ​3.72° to 115.85 ​± ​3.36° as cathodes for AZIBs has been investigated, where the corresponding battery performance shows a parabola trend with the peak in 103.04 ​± ​2.91°. The cathode achieves a high capacity of 384 ​mAh g−1 at 1 ​C and features an ultra-long lifetime of over 5000 cycles at 20 ​C, representing excellent Zn storage performance. A combination of experimental measurements and density functional theory calculations suggests that increased cathode hydrophobicity forces hydrated Zn2+ desolvation at electrode-electrolyte interface, facilitating zinc-ion insertion into host materials, yet extremely hydrophobic cathode leads to sluggish electrochemical kinetics. This study opens a new idea in the design of promising candidates for developing low cost and long lifespan batteries for aqueous systems.

Space-based optical (SBO) sensor is a special kind of star sensor, which can be used in not only the space-based observation for space objects but also satellite navigation, called optical navigation in this paper. The aim of this paper is to design optical navigation strategy for low earth orbit (LEO) satellites, including the selection of beacon objects, and the sensor scheduling for improving navigation accuracy. The processing and observation geometry of space-based optical observation is illustrated first. Based on the characteristics of the space-based optical observation, the distribution of beacon geosynchronous orbit satellites is designed for optical navigation of LEO satellites. And the sensor scheduling criterion for optical navigation is deduced to analyze the characteristics of optical navigation and schedule the navigation mission. It is found that an efficient way to improve the optical navigation accuracy is to add an additional sensor to track other beacon objects, whose line of sight (LOS) should be perpendicular to the original LOS of the sensor as far as possible. Therefore, global positioning system satellites are used as the supplement of beacon objects. Finally, based on the sensor scheduling criterion, navigation for a LEO satellite with two SBO sensors is scheduled, which obtains more accurate results and converges more rapidly.

The role of negative charges on cellulose nanowhiskers (CNWs) in the aqueous dispersion behaviors of graphene has been investigated. The sulfate groups were partially removed from the CNWs with sodium hydroxide solution. Both CNWs and desulfated cellulose nanowhiskers (D-CNWs) were applied in the aqueous dispersion process of graphene. The dispersing result was evaluated by ultraviolet-visible (UV-Vis) absorption spectra. It revealed the dispersing ability of D-CNWs became worse due to the removal of sulfate groups. It demonstrated the negative charged sulfate groups on CNWs played an important role in the graphene dispersing process.

Two-dimensional transition metal carbides (nitrides) MXenes have excellent electrochemical properties and be hoped as a promising electrode material for supercapacitors. However, MXene nanosheets are prone to aggregate due to van der Waals interaction, which affect its electrochemical performance. In this study, nitrogen-doped Ti3C2 (N-Ti3C2), which hydrothermally prepared from MXene Ti3C2, was assembled with metallic zinc to obtain a hybrid capacitor system in 1 M ZnSO4 aqueous electrolyte. In the voltage range of 0.05–1.2 V, the specific capacitance of this capacitor can reach 247.9 F g−1 (corresponding to an energy of 45.54 Wh kg−1). At high current density, it can quickly charge and discharge in 27 s, accompanied a high power output of 4093 W kg−1 and an energy of 30.99 Wh kg−1. It presents an outstanding cycling stability with 88.34% capacity retention over 6000 cycles. The self-discharge rate in 240 h is only 1.24 mV h−1. The high electrochemical performance mainly based on the introduction of nitrogen heteroatoms in cathode of N-Ti3C2, which show the ion adsorption/desorption, and the deposition/exfoliation of Zn (Zn2+) on the Zn anode to combine a hybrid capacitor.

Aqueous rechargeable sodium ion batteries (ASIBs) are low-cost and highly safe, which deserves more research in electrochemical energy storage systems. However, the developments of ASIBs are limited by its narrower thermodynamic voltage window (1.23 V) and lower energy density compared to the organic system. Therefore, widening the stable window of aqueous electrolyte and finding the new electrode materials of high capacity have become the focus of ASIBs researches. This review overviews the recent developments in electrode materials, and strategies for widening the stable window of aqueous electrolyte and constructing long-life for ASIBs. This review also briefly discusses the future challenges and perspectives of ASIBs.