Engineering multifunctional superstructure cathodes to conquer the critical issue of sluggish kinetics and large volume changes associated with divalent Zn-ion intercalation reactions is highly desirable for boosting practical Zn-ion battery applications. Herein, it is demonstrated that a MoS2/C19H42N+ (CTAB) superstructure can be rationally designed as a stable and high-rate cathode. Incorporation of soft organic CTAB into a rigid MoS2 host forming the superlattice structure not only effectively initiates and smooths Zn2+ transport paths by significantly expanding the MoS2 interlayer spacing (1.0 nm) but also endows structural stability to accommodate Zn2+ storage with expansion along the MoS2 in-plane, while synchronous shrinkage along the superlattice interlayer achieves volume self-regulation of the whole cathode, as evidenced by in situ synchrotron X-ray diffraction and substantial ex situ characterizations. Consequently, the optimized superlattice cathode delivers high-rate performance, long-term cycling stability (∼92.8% capacity retention at 10 A g–1 after 2100 cycles), and favorable flexibility in a pouch cell. Moreover, a decent areal capacity (0.87 mAh cm–2) is achieved even after a 10-fold increase of loading mass (∼11.5 mg cm–2), which is of great significance for practical applications. This work highlights the design of multifunctional superlattice electrodes for high-performance aqueous batteries.

In situ synthesized carbon nanofibers@NiSe core/sheath nanostructures act as robust and stable electrocatalysts for highly selective methanol conversion to value-added formate and boosting hydrogen production with less energy consumption.

Aqueous zinc batteries (AZBs) are considered promising candidates for large-scale energy storage systems because of their low cost and high safety. However, currently developed AZB cathodes always suffer from the intense charge repulsion of multivalent-ion and complex multiphase electrochemistry, resulting in an insufficient cycling life and impracticable high-sloping discharge profile. Herein, we found that the synthesized ultrathin Bi2O2Se nanosheets can effectively activate stable protons storage in AZBs rather than large zinc ions. This proton-dominated cathode provides an ultraflat discharge plateau (72% capacity proportion) and exhibits long-term cyclability as 90.64% capacity retention after 2300 cycles at 1 A g–1. Further in situ synchrotron X-ray diffraction, ex situ X-ray photoelectronic spectroscopy, and density functional theory confirm the energy storage mechanism regarding the highly reversible proton insertion/extraction process. Benefiting from the proton-dominated fast dynamics, reliable energy supply (>81.5% discharge plateau capacity proportion) is demonstrated at a high rate of up to 10 A g–1 and in the frozen electrolyte below −15 °C. This work provides a potential design of high-performance electrode materials for AZBs.

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Aqueous Zn‐ion batteries (AZIBs) are promising candidates for implementing large‐scale energy storage, but the adverse side reactions and unsatisfactory cycle life brought by Zn‐metal anodes limit their potential in applications. Herein, an ingenious synthesized CuS1–x@polyaniline (PANI) is proposed as an attractive conversion‐type Zn‐metal‐free anode for AZIBs, in which appropriate S‐vacancies and PANI heterointerfaces can be simultaneously constructed. This “killing three birds with one stone” strategy stabilizes the anode structure by utilizing organic–inorganic heterointerfaces and enhances Zn2+ storage, benefiting from abundant S‐vacancies, as well as initiating fast Zn2+ transport kinetics based on the joint effect of the two. Operando X‐ray absorption fine structure and synchrotron X‐ray diffraction further reveal the highly reversible conversion reaction of CuS1–x@PANI via a distinct crystallization–amorphous transformation mechanism. These features endow CuS1–x@PANI with sufficient zinc‐ion storage capacity (215 mA h g−1 at 100 mA g−1) and reliable current abuse tolerance (154.3 mA h g−1 at 1 A g−1 after 1000 cycles). Moreover, when matched with the optimized ZnxMnO2 cathode, the full battery achieves a record‐high cycling performance of 10 000 cycles (80% capacity retention) at a superhigh current density of 10 A g−1. This study provides new opportunities for developing high‐performance rocking‐chair AZIBs.