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The physical and chemical properties of electrolytes have significant impacts on battery performance. The concept of nanoconfinement has been proposed as an innovative modification strategy to address challenges related to the thermal stability, ion transport efficiency, and electrochemical stability of electrolytes. This involves confining electrolytes within nanoscale or sub-nanoscale spaces, leading to improvements in their physicochemical properties, such as increased boiling points, optimized ion migration, regulated ion concentration gradients, effective ion sieving, accelerated charge transfer, and suppressed side reactions. In this perspective article, we highlight the substantial potential of these approaches for extending the cycle life, broadening operational conditions, and enhancing the safety of lithium-based batteries. Additionally, the challenges and future research directions in this area are discussed. 

Abstract Matching the capacity of the anode and cathode is essential for maximizing electrochemical cell performance. This study presents two strategies to balance the electrode utilization in zinc ion supercapacitors, by decreasing dendritic loss in the zinc anode while increasing the capacity of the activated carbon cathode. The anode current collector was modified with copper nanoparticles to direct zinc plating orientation and minimize dendrite formation, improving the Coulombic efficiency and cycle life. The cathode was activated by an electrolyte reaction to increase its porosity and gravimetric capacity. The full cell delivered a specific energy of 192 ± 0.56 Wh kg⁻¹at a specific power of 1.4 kW kg⁻¹, maintaining 84% capacity after 50,000 full charge-discharge cycles up to 2 V. With a cumulative capacity of 19.8 Ah cm⁻²surpassing zinc ion batteries, this device design is particularly promising for high-endurance applications, including un-interruptible power supplies and energy-harvesting systems that demand frequent cycling. 

Abstract Developing suitable cathodes of sodium‐ion batteries (SIBs) with robust electrochemical performance and industrial application potential is crucial for the commercialization of large‐scale stationary energy storage systems. Layered sodium transition metal oxides, Na_xTmO₂(Tm representing transition metal), possessing considerable specific capacity, high operational potential, facile synthesis, cost‐effectiveness, and environmentally friendly characteristics, stand out as viable cathode materials. Nevertheless, the prevailing challenge of air‐induced degradation in most Na_xTmO₂significantly increases costs associated with production, storage, and transportation, coupled with a rapid decay in reversible capacity. This inherent obstacle inevitably impedes the advancement and commercial viability of SIBs. To address this challenge, it is essential to decode the chemistry of degradation caused by air exposure and develop protective strategies accordingly. In this review, a comprehensive and in‐depth understanding of the fundamental mechanisms associated with air‐induced degradation is provided. Additionally, the current state‐of‐the‐art effective protective strategies are explored and discuss the corresponding sustainability and scalability features. This review concludes with an outlook on present and future research directions concerning air‐stable cathode materials, offering potential avenues for upcoming investigations in advancing alkali metal layered oxides. 

Abstract In this work, a novel version of macrocyclic arenes, namely leaning pillar[6]arenes, was discovered and it can be considered as a tilted version of a pillar[6]arene with two hydroxy/alkoxy functionalities removed. Through a facile two‐step synthetic approaches, in conjunction with a diversity of post‐modification possibilities, a series of leaning pillar[6]arenes, with good cavity adaptability and enhanced guest‐binding capability, was synthesized, and their self‐assembly in single‐crystal states is presented. DFT calculations demonstrated that the lower rotational barrier of unsubstituted phenylene rings, the uneven electron density centered at the leaning phenyl rings, and the polarization effect along the edge generated by the hydrogen‐bond‐induced orientation of hydroxy groups greatly affected the host‐guest properties, and meanwhile provided an intuitive explanation for the pillar‐like and rigid structure of traditional pillar[6]arenes. Significantly, the crystal structure of cyclo‐oligomeric quinone was obtained by direct oxidation of leaning pillar[6]arenes.