The urgent demand for high-energy-density storage systems evokes the research upsurge on the alkali metal batteries with high theoretical capacities. However, the utilization of alkali metal anodes, including Li, Na, and K, is significantly hindered by notorious dendrite growth, undesirable corrosion, and unstable solid electrolyte interface. In order to resolve these issues, the carbon materials for the rational design of current collector/host that can regulate the plating/stripping behavior of alkali metal have been exploited. These carbon-based current collectors/hosts are featured with many pivotal advantages, including mechanical integrity to accommodate the volume change, superior electronic/ionic conductivity, large available surface area, and rich functionalization chemistries to increase the affinity to alkali metal. In this review, the recent progress on various dimensional carbon-based current collectors/hosts with different chemical components in stabilizing the alkali metal anodes through the regulation of initial deposition and subsequent growth behavior during plating/stripping process is provided. The nanostructured carbon scaffolds with self-affinity to alkali metals, as well as the carbon frameworks with internal/external affinitive sites to alkali metals, catalogued by various dimensions, are discussed in this review. Therefore, these appealing strategies based on the carbon-based current collectors/hosts can provide a paradigm for the realization of high-energy-density alkali metal batteries.

The deep understanding about the electrochemical behavior of the nanostructured electrode in electrolytes provides crucial insights for the rational design of electrode for sodium (Na)-ion storage system (NIS). Here, we report redox charge transfer kinetics and reversibility of VO₂(B) nanorod electrodes in both aqueous and organic electrolytes for NIS. The as-synthesized VO₂(B) nanorods show the reversible redox reaction with the higher specific and rate capacitances at high current density in aqueous electrolytes than in organic electrolytes. Temperature-dependent impedance measurements demonstrate the more facile interfacial charge transfer of Na ions into VO₂(B) nanorods in aqueous electrolytes. The reversible evolution in oxidation state and chemical composition of VO₂(B) nanorods is observed in aqueous electrolytes, as confirmed by ex situ XRD and ex situ X-ray photoelectron spectroscopy analyses. Given by the facile and reversible pseudocapacitive feature, the electrochemical performances of VO₂(B) nanorods are further improved by constructing the hierarchical structure of the reduced graphene oxide-VO₂ composite for aqueous Na⁺ ion storage.

Lithium–sulfur batteries (LSBs) are regarded as promising candidates for the next-generation energy storage devices owing to their high-theoretical capacity (1675 mAh g⁻¹) and affordable cost. However, several limitations of LSBs such as the lithium polysulfide shuttle, large volume expansion, and low electrical conductivity of sulfur need to be resolved for practical applications. To address these limitations, herein, a multidimensional architectured hybrid (Co@CNT/nG), where Co₃O₄ nanoparticles are encapsulated into three-dimensional (3D) porous N-doped reduced graphene oxide interconnected with carbon nanotube (CNT) branches, is synthesized through a simple pyrolysis method. The synergistic effect achieved through the homogeneously distributed and encapsulated Co₃O₄ nanoparticles, the interconnected CNT branches, and the 3D hierarchical porous structure and N-doping of Co@CNT/nG significantly suppresses the shuttle effect of lithium polysulfides and enhances the conversion redox kinetics for the improved sulfur utilization. We validate this effect through various measurements including symmetric cells, Li₂S nucleation, shuttle currents, Tafel slopes, diffusion coefficients, and post-mortem analyses. Importantly, Co@CNT/nG-70S-based LSB cells achieve a high-specific capacity of 1193.1 mAh g⁻¹ at 0.1 C and a low capacity decay rate of 0.030% per cycle for 700 cycles at 5 C, delivering a high areal capacity of 5.62 mAh cm⁻² even with a loading of 6.5 mg cm⁻².