ZnS has great potentials as an anode for lithium storage because of its high theoretical capacity and resource abundance; however, the large volume expansion accompanied with structural collapse and low conductivity of ZnS cause severe capacity fading and inferior rate capability during lithium storage. Herein, 0D-2D ZnS nanodots/Ti3C2Tx MXene hybrids are prepared by anchoring ZnS nanodots on Ti3C2Tx MXene nanosheets through coordination modulation between MXene and MOF precursor (ZIF-8) followed with sulfidation. The MXene substrate coupled with the ZnS nanodots can synergistically accommodate volume variation of ZnS over charge–discharge to realize stable cyclability. As revealed by XPS characterizations and DFT calculations, the strong interfacial interaction between ZnS nanodots and MXene nanosheets can boost fast electron/lithium-ion transfer to achieve excellent electrochemical activity and kinetics for lithium storage. Thereby, the as-prepared ZnS nanodots/MXene hybrid exhibits a high capacity of 726.8 mAh g−1 at 30 mA g−1, superior cyclic stability (462.8 mAh g−1 after 1000 cycles at 0.5 A g−1), and excellent rate performance. The present results provide new insights into the understanding of the lithium storage mechanism of ZnS and the revealing of the effects of interfacial interaction on lithium storage performance enhancement.

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A function F (x, y, t) that assigns to each parameter t an algebraic curve F (x, y, t) = 0 is called a moving curve. A moving curve F (x, y, t) is said to follow a rational curveA new technique for finding the implicit equation of a rational curve based on the notion of moving conics that follow the curve is investigated. For rational curves of degree 2n with no base points the method of moving conics generates the implicit equation as the determinant of an n × n matrix, where each entry is a quadratic polynomial in x and y, whereas standard resultant methods generate the implicit equation as the determinant of a 2n × 2n matrix where each entry is a linear polynomial in x and y. Thus implicitization using moving conics yields more compact representations for the implicit equation than standard resultant techniques, and these compressed expressions may lead to faster evaluation algorithms. Moreover whereas resultants fail in the presence of base points, the method of moving conics actually simplifies, because when base points are present some of the moving conics reduce to moving lines.

Aqueous zinc-ion batteries (AZIBs) are attractive energy storage devices that benefit from improved safety and negligible environmental impact. The V2O5-based cathodes are highly promising, but the dissolution of vanadium is one of the major challenges in realizing their stable performance in AZIBs. Herein, we design a Ti3C2T x MXene layer on the surface of V2O5 nanoplates (VPMX) through a van der Waals self-assembly approach for suppressing vanadium dissolution during an electrochemical process for greatly boosting the zinc-ion storage performance. Unlike conventional V2O5/C composites, we demonstrate that the VPMX hybrids offer three distinguishable features for achieving high-performance AZIBs: (i) the MXene layer on cathode surface maintains structural integrity and suppresses V dissolution; (ii) the heterointerface between V2O5 and MXene enables improved host electrochemical kinetics; (iii) reduced electrostatic repulsion exists among host layers owing to the lubricating water molecules in the VPMX cathode, facilitating interfacial Zn2+ diffusion. As a result, the as-made VPMX cathode shows a long-term cycling stability over 5000 cycles, surpassing other reported V2O5-based materials. Especially, we find that the heterointerface between V2O5 and MXene and lubricated water molecules in the host can achieve an enhanced rate capability (243.6 mAh g–1 at 5.0 A g–1) for AZIBs.

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Graphite anodes show great potential for potassium storage, however, their capacity fades quickly owing to substantial interlayer expansion/shrinkage (i.e., up to 60%) induced structural degradation. Here, Ti3C2Tx MXene nanosheets are used as a fast electron/potassium‐ion dual‐function conductor to construct the framework of all‐integrated graphite nanoflake (GNF)/MXene (GNFM) electrodes. The continuous MXene framework constructs a 3D channel for fast electron/potassium‐ion transfer and endows GNFM electrodes with a high structural stability. Owing to this unique MXene framework, GNFM electrodes exhibit much enhanced potassium storage performances than that of the conventional polymer‐bonded electrodes even at high mass loadings. Moreover, GNFM electrodes also show impressive cyclability in non‐flammable electrolytes and are further used as anodes to assemble novel non‐flammable potassium‐ion capacitors that show an excellent cyclability and high energy/power densities (113.1 Wh kg–1 and 12.2 kW kg–1). New insights into phase transition mechanism in GNFM electrodes are verified by operando XRD. Density functional theory calculations demonstrate that MXene can promote electron transfer and potassium diffusion in the heterointerface between GNF and MXene. Therefore, the results demonstrate that all‐integrated GNFM electrodes designed with MXene as multifunctional frameworks provide a new paradigm for producing efficient potassium storage anodes.

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