Rechargeable aqueous zinc-ion batteries (RZIBs) provide a promising complementarity to the existing lithium-ion batteries due to their low cost, non-toxicity and intrinsic safety. However, Zn anodes suffer from zinc dendrite growth and electrolyte corrosion, resulting in poor reversibility. Here, we develop an ultrathin, fluorinated two-dimensional porous covalent organic framework (FCOF) film as a protective layer on the Zn surface. The strong interaction between fluorine (F) in FCOF and Zn reduces the surface energy of the Zn (002) crystal plane, enabling the preferred growth of (002) planes during the electrodeposition process. As a result, Zn deposits show horizontally arranged platelet morphology with (002) orientations preferred. Furthermore, F-containing nanochannels facilitate ion transport and prevent electrolyte penetration for improving corrosion resistance. The FCOF@Zn symmetric cells achieve stability for over 750 h at an ultrahigh current density of 40 mA cm−2. The high-areal-capacity full cells demonstrate hundreds of cycles under high Zn utilization conditions.

In this study, ultrathin flexible RGO/CNF films with outstanding EMI shielding performances and strongly anisotropic thermal conductivity were successfully fabricated.

The development of Li−S batteries is largely impeded by the complicated shuttle effect of lithium polysulfides (LiPSs) and sluggish reaction kinetics. In addition, the low mass loading/utilization of sulfur is another key factor that makes Li−S batteries difficult to commercialize. Here, a porous catalytic V 2 O 3 / V 8 C 7 @carbon composite derived from MIL-47 (V) featuring heterostructures is reported to be an efficient polysulfide regulator in Li−S batteries, achieving a substantial increase in sulfur loading while still effectively suppressing the shuttle effect and enhancing kinetics. Systematic mechanism analyses suggest that the LiPSs strongly adsorbed on the V 2 O 3 surface can be rapidly transferred to the V 8 C 7 surface through the built-in interface for subsequent reversible conversion by an efficient catalytic effect, realizing enhanced regulation of LiPSs from capture to conversion. In addition, the porous structure provides sufficient sulfur storage space, enabling the heterostructures to exert full efficacy with a high sulfur loading. Thus, this S−V 2 O 3 /V 8 C 7 @carbon@graphene cathode exhibits prominent rate performance (587.6 mAh g −1 at 5 C) and a long lifespan (1000 cycles, 0.017% decay per cycle). It can still deliver superior electrochemical performance even with a sulfur loading of 8.1 mg cm −2 . These heterostructures can be further applied in pouch cells and produce stable output at different folding angles (0−180°). More crucially, the cells could retain 4.3 mAh cm −2 even after 150 cycles, which is higher than that of commercial lithium-ion batteries (LIBs). This strategy for solving the shuttle effect under high sulfur loading provides a promising solution for the further development of high-performance Li−S batteries.

3D thick electrode design is a promising strategy to increase the energy density of lithium-ion batteries but faces challenges such as poor rate and limited cycle life. Herein, a coassembly method is employed to construct low-tortuosity, mechanically robust 3D thick electrodes. LiFe 0.7 Mn 0.3 PO 4 nanoplates (LFMP NPs) and graphene are aligned along the growth direction of ice crystals during freezing and assembled into sandwich frameworks with vertical channels, which prompts fast ion transfer within the entire electrode and reveals a 2.5-fold increase in ion transfer performance as opposed to that of random structured electrodes. In the sandwich framework, LFMP NPs are entrapped in the graphene wall in a "plate-on-sheet" contact mode, which avoids the detachment of NPs during cycling and also constitutes electron transfer highways for the thick electrode. Such vertical-channel sandwich electrodes with mass loading of 21.2 mg cm −2 exhibit a superior rate capability (0.2C-20C) and ultralong cycle life (1000 cycles). Even under an ultrahigh mass loading of 72 mg cm −2 , the electrode still delivers an areal capacity up to 9.4 mAh cm −2 , ≈2.4 times higher than that of conventional electrodes. This study provides a novel strategy for designing thick electrodes toward high performance batteries.

In situ formed LiF grains are confined and evenly distributed throughout a covalent organic framework (COF) film, which exhibits cooperative effectiveness to greatly stabilize the lithium metal.

The performance of lithium–sulfur (Li–S) batteries is largely hindered by the shuttle effect caused by the dissolution of lithium polysulfides (LiPSs) and the sluggish reaction kinetics of LiPSs. Here, it is demonstrated that the nickel–cobalt double hydroxide (NiCo‐DH) shells that encapsulate sulfur nanoparticles can play multiple roles in suppressing the shuttle effect and accelerating the redox kinetics of LiPSs by combining with graphene and carbon nanotubes to construct the conductive networks. The NiCo‐DH shell that intimately contacts with sulfur physically confines the loss of sulfur and promotes the charge transfer and ion diffusion. More importantly, it can react with LiPSs to produce the surface‐bound intermediates, which are able to anchor the soluble LiPSs and accelerate the redox kinetics. Such composite electrodes can load high contents of sulfur (>85 wt%) and the resulting Li–S battery exhibits a superior capacity (1348.1 mAh g−1 at 0.1 C), ultrahigh rate performance (697.7 mAh g−1 at 5 C), and ultralong cycle life (1500 cycles) with a decay rate of 0.015% per cycle.

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