Lithium-sulfur battery represents a promising class of energy storage technology owing to its high theoretical energy density and low cost. However, the insulating nature, shuttling of soluble polysulfides and volumetric expansion of sulfur electrodes seriously give rise to the rapid capacity fading and low utilization. In this work, these issues are significantly alleviated by both physically and chemically restricting sulfur species in fluorinated porous triazine-based frameworks (FCTF-S). One-step trimerization of perfluorinated aromatic nitrile monomers with elemental sulfur allows the simultaneous formation of fluorinated triazine-based frameworks, covalent attachment of sulfur and its homogeneous distribution within the pores. The incorporation of electronegative fluorine in frameworks provides a strong anchoring effect to suppress the dissolution and accelerate the conversion of polysulfides. Together with covalent chemical binding and physical nanopore-confinement effects, the FCTF-S demonstrates superior electrochemical performances, as compared to those of the sulfur-rich covalent triazine-based framework without fluorine (CTF-S) and porous carbon delivering only physical confinement. Our approach demonstrates the potential of regulating lithium-sulfur battery performances at a molecular scale promoted by the porous organic polymers with a flexible design.

The development of ultrastable carbon materials for potassium storage poses key limitations caused by the huge volume variation and sluggish kinetics.N itrogen-enriched porous carbons have recently emerged as promising candidates for this application;h owever,r ational control over nitrogen doping is needed to further suppress the long-term capacity fading. Here we propose astrategy based on pyrolysis-etching of apyridine-coordinated polymer for deliberate manipulation of edge-nitrogen doping and specific spatial distribution in amorphous high-surface-area carbons;t he obtained material shows an edge-nitrogen content of up to 9.34 at %, richer N distribution inside the material, and high surface area of 616 m 2 g À1 under ac ost-effective low-temperature carbonization. The optimizedc arbon delivers unprecedented K-storage stability over 6000 cycles with negligible capacity decay (252 mA hg À1 after 4months at 1Ag À1), rarely reported for potassium storage.

Enhancing ionic conductivity of quasi‐solid‐state electrolytes (QSSEs) is one of the top priorities, while conventional metal–organic frameworks (MOFs) severely impede ion migration due to their abundant grain boundaries. Herein, ZIF‐4 glass, a subset of MOFs, is reported as QSSEs (LGZ) for lithium‐metal batteries. With lean Li content (0.12 wt%) and solvent amount (19.4 wt%), LGZ can achieve a remarkable ion conductivity of 1.61 × 10−4 S cm−1 at 30 °C, higher than those of crystalline ZIF‐4‐based QSSEs (LCZ, 8.21 × 10−5 S cm−1) and the reported QSSEs containing high Li contents (0.32–5.4 wt%) and huge plasticizer (30–70 wt%). Even at −56.6 °C, LGZ can still deliver a conductivity of 5.96 × 10−6 S cm−1 (vs 4.51 × 10−7 S cm−1 for LCZ). Owing to the grain boundary‐free and isotropic properties of glassy ZIF‐4, the facilitated ion conduction enables a homogeneous ion flux, suppressing Li dendrites. When paired with LiFePO4 cathode, LGZ cell demonstrates a prominent cycling capacity of 101 mAh g−1 for 500 cycles at 1 C with the near‐utility retention, outperforming LCZ (30.7 mAh g−1) and the explored MOF‐/covalent–organic frameworks (COF)‐based QSSEs. Hence, MOF glasses will be a potential platform for practical quasi‐solid‐state batteries in the future.

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Size tailored black BiVO4 colloids with rich oxygen vacancies were generated via facile laser processing for high performance sodium storage.

Ti4O7 nanoparticles grown on hollow carbon spheres through the carbothermal reduction reaction exhibit high sulfur loading, superior reversible capacity and favorable cycling stability.

Sluggish reaction kinetics induced by the poor solid-state ion diffusion and low electrical conductivity of electrode materials are currently in conflict with increasing fast-charge needs for sodium-ion batteries (SIBs) based on conversion mechanism. Herein, mesoporous, conductive, thin-wall three-dimensional (3D) skeletons of molybdenum nitride (meso-Mo2N) were established and employed as anodes to facilitate the rate performance of SIBs. Mesoporous channels (∼9.3 nm) with very thin walls (<8 nm) and conductive networks in meso-Mo2N enable the rapid Na+ infiltrability/diffusion and fast electron migration, respectively. The facilitated ion diffusion/transfer ability is corroborated by cyclic voltammetry tests and galvanostatic intermittent titration technique with a higher Na+ diffusion coefficient and a larger Na+ diffusion-dominated capacity. Consequently, meso-Mo2N exhibits a superior rate capability and a steady specific capacity of 158 mAh g–1 at 1 A g–1 after 1000 cycles for SIBs, surpassing the nonporous Mo2N and even the previously reported Mo2N. Furthermore, the proof of concept can be also extended to enhanced Li storage. Such a mesostructured design with 3D mesoporous, conductive thin walls of electrodes is a promising strategy for achieving fast-charging and high-performance Na/Li storage.