Embedding metal species into zeolite frameworks can create framework-bond metal sites in a confined microenvironment. The metals sitting in the specific T sites of zeolites and their crystalline surroundings are both committed to the interaction with the reactant, participation in the activation, and transient state achievement during the whole catalytic process. Herein, we construct isolated Co-motifs into purely siliceous MFI zeolite frameworks (Co-MFI) and reveal the location and microenvironment of the isolated Co active center in the MFI zeolite framework particularly beneficial for propane dehydrogenation (PDH). The isolated Co-motif with the distorted tetrahedral structure ({(SiO)2Co­(HO–Si)2}, two Co–O–Si bonds, and two pseudobridging hydroxyls (Co···OH–Si) is located at T1(7) and T3(9) sites of the MFI zeolite. DFT calculations and deuterium-labeling reactions verify that the isolated Co-motif together with the MFI microenvironment collectively promotes the PDH reaction by providing an exclusive microenvironment to preactivate C3H8, polarizing the oxygen in Co–O–Si bonds to accept H* ({(SiO)­CoHδ− (Hδ+O–Si)3}), and a scaffold structure to stabilize the C3H7* intermediate. The Co-motif active center in Co-MFI goes through the dynamic evolutions and restoration in electronic states and coordination states in a continuous and repetitive way, which meets the requirements from the series of elementary steps in the PDH catalytic cycle and fulfills the successful catalysis like enzyme catalysis.

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.

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