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In this study, we evaluate the two years (from 1 May 2019 to 30 April 2021) global operational sea surface wind speed (SWS) product of Fengyun-3D (FY-3D) polar-orbit meteorological satellite microwave radiation imager (MWRI) using ERA-5 reanalysis data. The total mean bias error (MBE), mean absolute error (MAE) and correlation coefficient of FY-3D/MWRI SWS product are −0.432 ± 3.09 m/s, 1.896 ± 2.50 m/s and 0.76, respectively. The current FY-3D/MWRI SWS data are comparable with the wind speed data of ERA-5 at most of the sea areas, especially the farther offshore sea areas. However, we still find significant overestimations (more than 5 m/s) near the coasts and typical differences in horizontal MBE values in different ascending and descending orbits. Besides, the rainy pixels as another negative impact factor are also common in FY-3D/MWRI SWS product, which can induce manifest overestimations of SWS. Therefore, the future FY-3/MWRI SWS operational algorithm should further develop a rigorous and robust quality-control module and a joint rainy pixel identification algorithm to better eliminate the unreasonable (or anomalous) pixels and rainy pixels. Moreover, the detailed evaluation on the on-orbit calibration performance of MWRI sensor is also necessary for both ascending and descending orbits. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) battery is recognized as the most promising next-generation energy storage system due to its high theoretical capacity and energy density. However, the shuttle effect of lithium polysulfides (LiPSs) and the sluggish electrochemical reaction kinetics severely hinder its practical application. In this study, a hierarchical porous carbon (HPC) conductive framework loaded with ZnS-SnO 2 heterostructures (ZnS-SnO 2 /HPC) in situ was designed for application in Li-S batteries. The ZnS-SnO 2 /HPC combines the advantages of physical confinement, chemical anchoring, and rapid electron/ion migration to inhibit the shuttling of LiPSs while ensuring its rapid conversion, achieving effective regulation of the electrochemical behavior of LiPSs. The obtained lithium-sulfur battery has significantly improved electrochemical properties: high reversible capacity (868.2 mAh g−1 after 100 cycles at 0.2 C), excellent rate capacity (841.5 mAh g−1 at 3 C), and low self-discharge capacity loss (97% capacity retention after 5 days of standing). In addition, the synergistic effect also helps to improve the cycle stability, with a capacity fading rate of only 0.079% per cycle over 500 cycles at 1 C. ● The ZnS-SnO 2 heterostructure nanoparticles are uniformly attached to the surface of hierarchical porous carbon. ● The Li-S batteries with ZnS-SnO 2 /HPC@PP exhibit an excellent cycling and rate performance. ● The shuttle effect is alleviated by the strong adsorption capacity of SnO 2 and the good catalytic activity of ZnS. ● At a high sulfur load of 4.73 mg cm−2, the battery's capacity can be maintained at 865.3 mAh g−1 after 50 cycles at 0.1 C. [ABSTRACT FROM AUTHOR]

The preparation of composite carbon nanomaterials is one of the methods for improving the electrochemical performance of carbon-based electrode materials for supercapacitors. However, traditional preparation methods are complicated and time-consuming, and the binder also leads to an increase in impedance and a decrease in specific capacitance. Therefore, in this work, we reduced Ni-Cu nanoparticles on the surface of nitrogen-doped carbon nanofibers (CNFs) by employing an electrostatic spinning method combined with pre-oxidation and annealing treatments. At the same time, Ni-Cu nanoparticles were vulcanized to Ni–Cu–S nanoparticles without destroying the structure of the CNFs. The area-specific capacitance of the CNFs/Ni–Cu–S–300 electrode reaches 1208 mF cm−2 at a current density of 1 mA cm−2, and the electrode has a good cycling stability with a capacitance retention rate of 76.5% after 5000 cycles. As a self-supporting electrode, this electrode can avoid the problem of the poor adhesion of electrode materials and the low utilization of active materials due to the inactivity of the binder and conductive agent in conventional collector electrodes, so it has excellent potential for application. [ABSTRACT FROM AUTHOR]

Lithium-sulfur (Li–S) batteries have attracted much attention due to high energy density and low cost. However, some vital issues, especially the notorious shuttle effect of polysulfides has greatly hindered the practical development of Li–S batteries. Reasonable design of electrocatalysts to improve the electrochemical performance of Li–S batteries by enhancing the chemical immobilization and catalytic conversion of polysulfides is considered as a promising solution. Herein, an integrated structure consisting of reduced graphene oxide (RGO) nanosheets modified with Co 9 S 8 nanoparticles is reported, which is expected to be used as a mediator for Li–S batteries to improve the anchoring and catalyzing of polysulfides. The Co 9 S 8 nanoparticles not only have excellent chemisorption capability to capture polysulfides, but also can be used as catalysts to accelerate the conversion of polysulfides. Highly conductive RGO nanosheets can provide appropriate ion/electron diffusion path length, facilitate interfacial reaction kinetics and physically limit polysulfide diffusion. Accordingly, the as-assembled Li–S battery has excellent cycling stability with a low capacity decay rate of 0.041% per cycle over 1000 cycles at 3 A g−1. Importantly, it enables the device to operate over a wide temperature range, with an area specific capacity of 6.4 mAh cm−2 at a sulfur load of 5.8 mg cm−2. [Display omitted] • A functionalized separator is constructed to intercept and catalyze polysulfides. • The Co 9 S 8 nanoparticles effectively improve the reaction kinetics of polysulfides. • Co 9 S 8 shows strong chemical interaction with polysulfides during cycle process. • The designed Li–S batteries exhibit enhanced capacities and cyclic stabilities. [ABSTRACT FROM AUTHOR]