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The vanadium redox flow battery (VRFB) holds promise for large‐scale energy storage applications, despite its lower energy and power densities compared to advanced secondary batteries available today. Carbon materials are considered suitable catalyst electrodes for improving many aspects of the VRFB. However, pristine graphite structures in carbon materials are catalytically inert and require modification to activate their catalytic activity. Among the various strategies developed so far, O‐functionalization and chemical doping of carbon materials are considered some of the most promising pathways to regulate their electronic structures. Building on the catalytic mechanisms involved in the VRFB, this concise review discusses recent advancements in the O‐functionalization and chemical doping of carbon materials. Furthermore, it explores how these materials can be tailored and highlights future directions for developing more promising VRFBs to guide future research. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (SIBs) are promising alternatives to lithium‐ion batteries with similar working principles, cell structures, and material systems. However, attaining long‐term stability and high‐capacity performance of SIBs at ultrahigh rates remains a significant challenge due to the large ionic radius and slow kinetic behavior of Na+. Herein, a novel robust anode with a dual‐biomimetic gradient hierarchical architecture is proposed and provide a simple strategy to fabricate this sulfur‐doped mesoporous carbon concave hollow sphere/Ti3C2Tx MXene (SCMX) anode. In addition, Cu2S nanoparticles are in situ embedded into the SCMX architecture by electrochemical induction during the cycling process to act as active sites, which enhances the rate performance and cycling stability. Relying on its hybrid architecture and in situ formed Cu2S, this SCMX anode can achieve high ion accessibility, rich active sites, rapid charge transfer, and favorable structure stability, as disclosed by in/ex situ characterizations. As a result, it exhibits high reversible capacity (745.6 mAh g−1 at 0.2 A g−1), ultrahigh‐rate capability (380.5 mAh g−1 at 50.0 A g−1), and long cycling stability (98.2% capacity retention after 10 000 cycles at 80.0 A g−1). This work is anticipated to accelerate the development of high‐performance SIBs and offer distinctive inspiration for the design of electrode structures/systems. [ABSTRACT FROM AUTHOR]

Aqueous Zn‐metal batteries (AZMBs) have gained great interest due to their low cost, eco‐friendliness, and inherent safety, which serve as a promising complement to the existing metal‐based batteries, e.g., lithium‐metal batteries and sodium‐metal batteries. Although the utilization of aqueous electrolytes and Zn metal anode in AZMBs ensures their improved safety over other metal batteries meanwhile guaranteeing their decent energy density at the cell level, plenty of challenges involved with metallic Zn anode still await to be addressed, including dendrite growth, hydrogen evolution reaction, and zinc corrosion and passivation. In the past years, several attempts have been adopted to address these problems, among which engineering the aqueous electrolytes and additives is regarded as a facile and promising approach. In this review, a comprehensive summary of aqueous electrolytes and electrolyte additives will be given based on the recent literature, aiming at providing a fundamental understanding of the challenges associated with the metallic Zn anode in aqueous electrolytes, meanwhile offering a guideline for the electrolytes and additives engineering strategies toward stable AZMBs in the future. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) 1H molybdenum disulfide (1H-MoS2) is hard to be directly used in energy storage devices due to its inert basal plane and unfavorable 2D stacking. This work demonstrated how the basal plane of 1H MoS2 nanocrystals (NCs) can be activated to offer doubled specific capacitance by simple surface S depletions. Building on the expanded graphene with three-dimensional (3D) structures, as-prepared NCs were chemically grafted on the graphene surface to deliver stable energy storage and high capacitance, which overcame above challenges of 1H-MoS2. Aside from the mostly focused metastable phase, this work confirmed that the stable 1H Mo–S material is also promising in energy storage applications. [ABSTRACT FROM AUTHOR]

The exploration of inexpensive and efficient catalysts for oxygen reduction reaction (ORR) is crucial for chemical and energy industries. Carbon materials have been proved promising with different catalysts enabling 2 and 4e− ORR. Nevertheless, their ORR activity and selectivity is still complex and under debate in many cases. Many structures of these active carbon materials are also chemically unstable for practical implementations. Unlike the well‐discussed structures, this work presents a strategy to promote efficient and stable 2e− ORR of carbon materials through the synergistic effect of lattice distortion and H‐passivation (on the distorted structure). We show how these structures can be formed on carbon cloth, and how the reproducible chemical adsorption can be realized on these structures for efficient and stable H2O2 production. The work here gives not only new understandings on the 2e− ORR catalysis, but also the robust catalyst which can be directly used in industry. [ABSTRACT FROM AUTHOR]

The exploration of inexpensive and efficient catalysts for oxygen reduction reaction (ORR) is crucial for chemical and energy industries. Carbon materials have been proved promising with different catalysts enabling 2 and 4e− ORR. Nevertheless, their ORR activity and selectivity is still complex and under debate in many cases. Many structures of these active carbon materials are also chemically unstable for practical implementations. Unlike the well‐discussed structures, this work presents a strategy to promote efficient and stable 2e− ORR of carbon materials through the synergistic effect of lattice distortion and H‐passivation (on the distorted structure). We show how these structures can be formed on carbon cloth, and how the reproducible chemical adsorption can be realized on these structures for efficient and stable H2O2 production. The work here gives not only new understandings on the 2e− ORR catalysis, but also the robust catalyst which can be directly used in industry. [ABSTRACT FROM AUTHOR]

The exploration of inexpensive and efficient catalysts for oxygen reduction reaction (ORR) is crucial for chemical and energy industries. Carbon materials have been proved promising with different catalysts enabling 2 and 4e− ORR. Nevertheless, their ORR activity and selectivity is still complex and under debate in many cases. Many structures of these active carbon materials are also chemically unstable for practical implementations. Unlike the well‐discussed structures, this work presents a strategy to promote efficient and stable 2e− ORR of carbon materials through the synergistic effect of lattice distortion and H‐passivation (on the distorted structure). We show how these structures can be formed on carbon cloth, and how the reproducible chemical adsorption can be realized on these structures for efficient and stable H2O2 production. The work here gives not only new understandings on the 2e− ORR catalysis, but also the robust catalyst which can be directly used in industry. [ABSTRACT FROM AUTHOR]

The exploration of inexpensive and efficient catalysts for oxygen reduction reaction (ORR) is crucial for chemical and energy industries. Carbon materials have been proved promising with different catalysts enabling 2 and 4e− ORR. Nevertheless, their ORR activity and selectivity is still complex and under debate in many cases. Many structures of these active carbon materials are also chemically unstable for practical implementations. Unlike the well‐discussed structures, this work presents a strategy to promote efficient and stable 2e− ORR of carbon materials through the synergistic effect of lattice distortion and H‐passivation (on the distorted structure). We show how these structures can be formed on carbon cloth, and how the reproducible chemical adsorption can be realized on these structures for efficient and stable H2O2 production. The work here gives not only new understandings on the 2e− ORR catalysis, but also the robust catalyst which can be directly used in industry. [ABSTRACT FROM AUTHOR]

The high‐rate cyclability of Li‐rich Mn‐based oxide (LMO) is highly limited by the electrochemical polarization resulting from the slow kinetic of the Li2MnO3 phase. Herein, the Prussian blue (PB) coating layer with specific redox potential is introduced as a functionalized interface to overcome the side effect and the escaping of O on the surface of LMO, especially its poor rate capability. In detail, the PB layer can restrict the large polarization of LMO by sharing overloaded current at a high rate due to the synchronous redox of PB and LMO. Consequently, an enhanced high rate performance with capacity retention of 87.8% over 300 cycles is obtained, which is superior to 50.5% of the pristine electrode. Such strategies on the high‐rate cyclability of Li‐rich Mn‐based oxide compatible with good low‐rate performances may attract great attention for pursuing durable performances. [ABSTRACT FROM AUTHOR]