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Porous carbon materials have demonstrated exceptional performance in various energy and environment-related applications. Recently, research on supercapacitors has been steadily increasing, and porous carbon materials have emerged as the most significant electrode material for supercapacitors. Nonetheless, the high cost and potential for environmental pollution associated with the preparation process of porous carbon materials remain significant issues. This paper presents an overview of common methods for preparing porous carbon materials, including the carbon-activation method, hard-templating method, soft-templating method, sacrificial-templating method, and self-templating method. Additionally, we also review several emerging methods for the preparation of porous carbon materials, such as copolymer pyrolysis, carbohydrate self-activation, and laser scribing. We then categorise porous carbons based on their pore sizes and the presence or absence of heteroatom doping. Finally, we provide an overview of recent applications of porous carbon materials as electrodes for supercapacitors. [ABSTRACT FROM AUTHOR]

When compared to expensive lithium metal, the metal sodium resources on Earth are abundant and evenly distributed. Therefore, low-cost sodium-ion batteries are expected to replace lithium-ion batteries and become the most likely energy storage system for large-scale applications. Among the many anode materials for sodium-ion batteries, hard carbon has obvious advantages and great commercial potential. In this review, the adsorption behavior of sodium ions at the active sites on the surface of hard carbon, the process of entering the graphite lamellar, and their sequence in the discharge process are analyzed. The controversial storage mechanism of sodium ions is discussed, and four storage mechanisms for sodium ions are summarized. Not only is the storage mechanism of sodium ions (in hard carbon) analyzed in depth, but also the relationships between their morphology and structure regulation and between heteroatom doping and electrolyte optimization are further discussed, as well as the electrochemical performance of hard carbon anodes in sodium-ion batteries. It is expected that the sodium-ion batteries with hard carbon anodes will have excellent electrochemical performance, and lower costs will be required for large-scale energy storage systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • The oxygen-defects enhance TiO 2 adsorption of polysulfides, thus effectively immobilize polysulfides and minimize the shuttle effect. • The oxygen-defects work as efficient catalytic active sites, promote the polysulfide conversion reaction kinetics. • The high electrical conductivity of nitrogen-doped mesoporous carbon maximizes the sulfur utilization. High-energy–density lithium-sulfur batteries have been rated as a promising, yet challenging, next-generation battery technology. Typically, the serious shuttle of polysulfide intermediates and sluggish solid–solid reaction kinetics often result in irreversibly sulfur loss, low Coulombic efficiency, and limited lifespan. Herein, we propose a facile and efficient separator modification strategy using a rationally designed sulfiphilic and lithiophilic mediator, i.e. in-situ confinement growth of oxygen-deficient TiO 2- x nanoparticles within nitrogen-doped mesoporous carbon matrix to modulate the sulfur electrochemistry. The nanoscale defective catalyst within open mesoporous host affords favorable adsorption of polysulfides and catalytic conversion ability. Moreover, the versatile composite improves the electrolyte wettability and Li+ transfer kinetics and alleviates self-discharge behavior. Resultantly, the Li-S batteries using modified separator achieves significantly improved cycling stability with a low capacity decay of only 0.067% per cycle after 500 cycles at 2C. The defect engineering together with separator modification strategies enable efficient and durable Li-S batteries. [ABSTRACT FROM AUTHOR]

With the increasing importance placed on resources and the environment, lithium-ion batteries have entered a stage of rapid development. However, the current reserves of lithium resources are unable to meet the future demand for large-scale energy storage. Therefore, exploring new energy storage technologies is of utmost urgency. Sodium-ion batteries, not only abundant in reserves and low in cost, but also share similar structural principles and characteristics with lithium-ion batteries, hold the promise of commercialization. The cathode material plays a crucial role in the performance of sodium-ion batteries. Among numerous materials, transition metal vanadates exhibit exceptional theoretical capacity and structural stability. In this study, MnV 2 O 6 /Graphene Oxide (MVO/GO) nanobelt composites were directly synthesized using a hydrothermal method. The large aspect ratio of the material can shorten the radial transport distance of ions, accelerate ion diffusion, and release stress in the axial direction during cycling. The gaps between nanobelts also facilitate the infiltration of the electrolyte, while the inclusion of graphene oxide provides structural support. The MVO/GO electrode has a high reversible specific capacity (323.8 mAh g−1 after 100 cycles at 100 mA g−1) and excellent long-term cycle performance (900 cycles at 2 A g−1 is 191.2 mAh g−1). • Nanoribbon-like MnV 2 O 6 attached to graphene oxide was synthesized. • The unique nanoribbon structure of MnV 2 O 6 has a shorter transmission distance in the radial direction. • Graphene oxide as a substrate can reduce the agglomeration of MnV 2 O 6 nanobelts. • The MVO/GO electrode has a high reversible specific capacity (323.8 mAh g−1 after 100 cycles at 100 mA g−1) and excellent long-term cycle performance (900 cycles at 2 A g−1 is 191.2 mAh g−1). [ABSTRACT FROM AUTHOR]