Carbon materials display appealing physical, chemical, and mechanical properties and have been extensively studied as supercapacitor electrodes. The surface engineering further allows us to tune their capability of adsorption/desorption and catalysis. Therefore, a facile and inexpensive chemical-acid-etching approach has been developed to activate the carbon cloth as an electrode for supercapacitor. The capacitance of the acid-etched carbon cloth electrode can approach 5310 mF cm–2 at a current density of 5 mA cm–2 with remarkable recycling stability. The all-solid-state symmetric supercapacitor delivered a high energy density of 4.27 mWh cm–3 at a power density of 1.32 W cm–3. Furthermore, this symmetric supercapacitor exhibited outstanding mechanical flexibility, and the capacity remained nearly unchanged after 1000 bending cycles.

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Aqueous zinc-ion batteries (ZIBs) are low cost with a promising theoretical capacity and inherent safety, and thus have drawn increasing attention as prospective energy storage devices in large-scale energy storage systems. However, severe dendrite growth and side reaction problems hinder the practical application of ZIBs. Here, molecular sieves with ordered mesoporous channels are constructed to tailor the local electrolyte solvation structure on the zinc surface. Different high-concentration solvation structures can be realized by adjusting the pore diameter of the molecular sieve, and the optimal pore geometry is a mesoporous channel with a diameter of 2.5 nm that induces the formation of a locally concentrated electrolyte and affords a lower Zn 2+ de-solvation energy in Mobil composition of matter number 41 (MCM41). The resulting MCM41-Zn anode exhibits high cycling stability for Zn stripping/plating under different current densities (over 1800 h at 1 mA cm -2 , 1 mAh cm -2 , and 2200 h at 5 mA cm -2 , 1 mAh cm -2 ). Moreover, the CaV 8 O 20 •nH 2 O//MCM41-Zn full cell shows a high capacity of 274.2 mAh g −1 and a long lifespan (no capacity decay after 1000 cycles at 4 A g -1 ).

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Pre‐intercalation of metal ions into vanadium oxide is an effective strategy for optimizing the performance of rechargeable zinc‐ion battery (ZIB) cathodes. However, the battery long‐lifespan achievement and high‐capacity retention remain a challenge. Increasing the electronic conductivity while simultaneously prompting the cathode diffusion kinetics can improve ZIB electrochemical performance. Herein, N‐doped vanadium oxide (N‐(Zn,en)VO) via defect engineering is reported as cathode for aqueous ZIBs. Positron annihilation and electron paramagnetic resonance clearly indicate oxygen vacancies in the material. Density functional theory (DFT) calculations show that N‐doping and oxygen vacancies concurrently increase the electronic conductivity and accelerate the diffusion kinetics of zinc ions. Moreover, the presence of oxygen vacancies substantially increases the storage sites of zinc ions. Therefore, N‐(Zn,en)VO exhibits excellent electrochemical performance, including a peak capacity of 420.5 mA h g−1 at 0.05 A g−1, a high power density of more than 10 000 W kg−1 at 65.3 Wh kg−1, and a long cycle life at 5 A g−1 (4500 cycles without capacity decay). The methodology adopted in our study can be applied to other cathodic materials to improve their performance and extend their practical applications.