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High rate tolerance and long cycle life represent the critical demand of the market for energy storage devices, known as one of major challenges for the development of rechargeable aqueous batteries. Herein, a layered Mo4/3B2T2 (where "T" denotes ‐O, ‐OH, and ‐F terminations) MBene (a transition metal boride) with in‐plane ordered metal vacancies is first proposed as an iodine species host of an aqueous Zn‖I2 battery, delivering a discharge capacity of 106.8 mAh g−1 at 25 A g−1 after 230 000 cycles and 80 mAh g−1 at 100 A g−1, far exceeding those of all Zn‖I2 batteries ever reported. The high performance is attributed to the strong affinity with iodine species and accelerated the redox kinetics by the conductive MBene with metal vacancies, as evidenced by the one‐step conversion of I‒/I0 without the generation of I3‒ ions. This work unlocks a new route for the construction of other halide or sulfur electrode batteries with superior durability and kinetics. [ABSTRACT FROM AUTHOR]

The formation and stability of the solid electrolyte interphase (SEI) play a crucial role in determining the performance and lifespan of lithium-ion batteries (LIBs) at evaluated temperatures. Electrolyte additives have emerged as promising candidates for modulating the formation kinetics and stability of the SEI layer. In this study, molecular dynamics (MD) and ab initio molecular dynamics (AIMD) simulations were employed to investigate the influences of P-toluenesulfonyl isocyanate (PTSI) as an electrolyte additive in the LiPF 6 /EC/DMC electrolyte on the SEI formation process on the graphite anode under high temperatures. MD simulations revealed that PTSI induces modifications in the solvation structure, resulting in two ethylene carbonate (EC) and two dimethyl carbonate (DMC) molecules in the first solvation shell of Li + . Furthermore, the PTSI additive suppressed the decomposition of solvent molecules and PF6 anions in the LiPF 6 /EC/DMC/PTSI electrolyte under high temperatures according to the AIMD simulations, contributing to a more stable SEI layer. Moreover, this suppression can be attributed to the reduced reactivity of solvent molecules and salt anions, as evidenced by the enhanced bond strength and decreased bond length. These microscopic insights provide a multi-faceted understanding of the functionality of PTSI additives, facilitating the rational design of novel additives., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Electrocatalytic reduction of dinitrogen to ammonia has attracted significant research interest. Herein, it reports the boosting performance of electrocatalytic nitrogen reduction on Ti 2 CO 2 MXene with an oxygen vacancy through biaxial tensile strain engineering. Specifically, tensile strain modified electronic structures and formation energy of oxygen vacancy are evaluated. The exposed Ti atoms with additional electron states near the Fermi level serve as active site for intermediate adsorption, leading to superior catalytic performance (U limit = -0.44 V) under 2.5% biaxial tensile strain through a distal mechanism. However, the two sides of the "Sabatier optimum" in volcano plot are not limited by two different electronic steps, but are induced by the diverse adsorption behaviors of intermediates. Crucially, the "Sabatier optimum" results from the different response speeds of the adsorption energy for *N 2 and *NNH to strains. Moreover, the authors observe conventional d-band adsorption for *N 2 and *NNH, non-linear adsorption for *NNH 2 , and abnormal d-band adsorption for *N, *NH, *NH 2 , and *NH 3 , which can be explained by the competition between attractive orbital hybridization and repulsive orbital orthogonalization with the spin-polarized d-band model, which further clarifies the contributions of 3σ → d z2 and d xz /d yz → 2π* to the overall population of bonding and anti-bonding states., (© 2023 Wiley-VCH GmbH.)