Jiawei Wang

A dynamic hydrogen bond bridging strategy is developed to simultaneously regulate the hydrogen evolution, dendrite growth, and by-product formation parasitic reactions of zinc metal anodes for high-performance aqueous zinc-ion batteries.

Aqueous zinc-ion batteries (AZIBs) have attracted considerable interest due to their intrinsic merits, such as excellent safety, affordability, and eco-friendliness. However, the practical deployment is greatly limited by H2O-induced parasitic reactions at the zinc metal anode (ZMA), such as the hydrogen evolution reaction (HER) and interfacial passivation. Herein, we propose a synergistic interfacial-regulation strategy to mitigate these parasitic reactions. By leveraging the zincophilic carboxyl groups and hydrophobic alkyl chains of straight-chain fatty acid (SFA) molecules, a H2O-shielding electric double layer (EDL) and a hydrophobic solid electrolyte interphase (SEI) are simultaneously constructed in situ at the ZMA|electrolyte interface. This integrated H2O-shielding EDL and hydrophobic SEI framework effectively suppresses H2O-induced parasitic reactions and enhances the stability of Zn2+ deposition, highlighting the critical role of coordinated regulation. Under optimal conditions using lauric acid (a C12-based SFA), the Zn||Zn symmetric cell delivers an exceptional reversible cycle life exceeding 5785 h at 1 mA cm−2 and 1 mA h cm−2. Furthermore, the full cell exhibits excellent cycling stability, retaining 75.4% of its initial capacity after 1500 stable cycles at 5 A g−1. This work provides a promising strategy for achieving stable, high-performance ZMA and opens avenues for advancing AZIBs technology.

Due to their unique electronic structures and polymorphic characteristics, transition metal sulfur compounds and their composite materials have a variety of functions and excellent prospects, which have attracted widespread attention this year, especially in research and application fields such as energy conversion and storage. Among them, the composition and structure of monovalent and binary transition metal sulfur/selenium compounds are relatively less complex. Their electrochemical and other related properties can easily be effectively regulated and optimized due to changes in parameters such as material composition, microstructure, and electronic structure. In the present work, a two-step hydrothermal route was used to construct a multiphase ZnS/ZnSe–MXene heterogeneous composite hybrid material via two-step hydrothermal treatment using ZIF-7 as the precursor. The obtained multidimensional hybrid architecture featuring a unique mesoporous network provides a specific surface area of 10.54 m2 g–1, with an average pore size of 3.68 nm. This optimized porous structure effectively facilitates electrolyte penetration and exposes a considerable number of redox-active sites, enabling the ZnS/ZnSe@MXene electrode to exhibit a gravimetric specific capacitance of 1047.2 F g–1 at a current density of 1 A g–1 with a three-electrode set up, and after experiencing up to 10,000 cycles at a high current density of 10 A g–1, its capacitance retention rate can still reach 88.78% of the initial capacitance. In addition, an asymmetric supercapacitor assembled by using ZnS/ZnSe@MXene serving as the positive electrode and straw-derived homemade activated carbon (AC) acting as the negative electrode can achieve an energy density of 15.5 Wh kg–1 (power density: 750 W kg–1), where energy and power densities are normalized to the total mass of active materials in the positive and negative electrodes. This work confirms that ZnS/ZnSe@MXene hybrid materials have broad prospects as electrode materials for advanced energy storage systems.