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NASICON‐type sodium vanadium phosphate (Na₃V₂(PO₄)₃, or NVP) cathode materials have great potential for fast charging and long cycling sodium‐ion batteries (SIBs) similar to lithium iron phosphate (LiFePO₄, or LFP) cathode materials used in lithium‐ion batteries (LIBs). However, the cycle life and energy density in the full cell using NVP materials need to be significantly improved. This paper investigates the degradation mechanisms of NVP‐based SIBs and identifies the Na loss from the cathode to the anode solid electrolyte interphase (SEI) reactions as the main cause of capacity degradation. A new Na‐rich NVP cathode (e.g., Na₄V₂(PO₄)₃, or Na₄VP) is developed to address the Na loss problem. Conventional NVP can be easily transformed into the Na₄VP by a facile and fast chemical solution treatment (30 s). Na‐free‐anode Na₄VP and hard carbon‐Na₄VP full cells are assembled to evaluate the electrochemical properties of the Na‐rich NVP cathode. The Na₄VP cathode provides excess Na to compensate for the Na loss, resulting much longer cycle life in the full cells (>400 cycles) and a high specific energy and power density. Good low‐temperature performance is also observed.

Core–shell magnetic porous microspheres have wide applications in drug delivery, catalysis and bioseparation, and so on. However, it is great challenge to controllably synthesize magnetic porous microspheres with uniform well‐aligned accessible large mesopores (>10 nm) which are highly desired for applications involving immobilization or adsorption of large guest molecules or nanoobjects. In this study, a facile and general amphiphilic block copolymer directed interfacial coassembly strategy is developed to synthesize core–shell magnetic mesoporous microspheres with a monolayer of mesoporous shell of different composition (FDUcs‐17D), such as core–shell magnetic mesoporous aluminosilicate (CS‐MMAS), silica (CS‐MMS), and zirconia‐silica (CS‐MMZS), open and large pores by employing polystyrene‐block‐poly (4‐vinylpyridine) (PS‐b‐P4VP) as an interface structure directing agent and aluminum acetylacetonate (Al(acac)₃), zirconium acetylacetonate, and tetraethyl orthosilicate as shell precursors. The obtained CS‐MMAS microspheres possess magnetic core, perpendicular mesopores (20–32 nm) in the shell, high surface area (244.7 m²g⁻¹), and abundant acid sites (0.44 mmol g⁻¹), and as a result, they exhibit superior performance in removal of organophosphorus pesticides (fenthion) with a fast adsorption dynamics and high adsorption capacity. CS‐MMAS microspheres loaded with Au nanoparticles (≈3.5 nm) behavior as a highly active heterogeneous nanocatalyst forN‐alkylation reaction for producingN‐phenylbenzylamine with a selectivity and yields of over 90% and good magnetic recyclability.