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Aqueous zinc (Zn) battery with remarkable advantages of high safety, low cost, and high reversibility is highly applauded in next‐generation low‐speed electric vehicles and large‐scale energy storage applications. However, Zn anode suffers from a series of unfavorable reactions, hindering its progress toward industrialization. Herein, a functionalized hydrogel film is designed using polydopamine and polyacrylamide crosslinking (PDAM) as the Zn protective layer to stabilize the Zn anode. Benefiting from the strong interaction of Zn2+ with PDAM, the primary solvation shell of Zn2+ is regulated by PDAM into the form of PDAM–Zn2+‐5H2O. This remodeling prevents Zn dendrite growth and inhibits water‐induced side reactions. As a result, the Zn–MnO2 battery using PDAM‐coated Zn anode exhibits excellent cycling stability, demonstrating over 1150 cycles at an areal capacity of 5 mAh cm−2 with an average Coulombic efficiency (CE) of 96.5%. For a scaled‐up PDAM@Zn–MnO2 pouch cell with a capacity of 80 mAh, stable cycling of over 200 cycles with an average CE of 91.9% is achieved. The superior Zn–MnO2 battery enabled by the functionalized hydrogel protective film enlightens an arena toward next‐generation energy storage applications. [ABSTRACT FROM AUTHOR]

Aqueous zinc–chlorine battery with high discharge voltage and attractive theoretical energy density is expected to become an important technology for large‐scale energy storage. However, the practical application of Zn–Cl2 batteries has been restricted due to the Cl2 cathode with sluggish kinetics and low Coulombic efficiency (CE). Here, an aqueous Zn–Cl2 battery using an inexpensive and effective MnO2 redox adsorbent (referred to Zn‐Cl2@MnO2 battery) to modulate the electrochemical performance of the Cl2 cathode is developed. Density functional theory calculations reveal that the existence of the intermediate state Clads free radical catalyzed by MnO2 on the Cl2 cathode contributes to the charge storage capacity, which is the key to modulate the electrode and improve the electrochemical performance. Further analysis of the Cl2 cathode kinetics discloses the adsorption and catalytic roles of the MnO2 redox adsorbent. The Zn–Cl2@MnO2 battery displays an enhanced discharge voltage of 2.0 V at a current density of 2.5 mA cm−2, and stable 1000 cycles with an average CE of 91.6%, much superior to the conventional Zn–Cl2 battery with an average CE of only 66.8%. The regulation strategy to the Cl2 cathode provides opportunities for the future development of aqueous Zn‐Cl2 batteries. [ABSTRACT FROM AUTHOR]

Metallic aluminum is an attractive anode owing to its high specific capacity, earth abundance, and low cost. However, the poor reversibility of Al deposition/dissolution and Al dendrites have impeded its deployment. Herein, a strategy for constructing a lattice‐matching layer (LML) to regulate the behavior of Al deposition/dissolution is demonstrated. Various experiments and theoretical calculations validate that gold LML as an example can significantly enhance the nucleation density and reduce average particle size, which achieve highly reversible, dendrite‐free, durable, and anode‐free Al anodes. The metallic Al shows stable Al deposition/dissolution on Au@Ti substrate for more than 4500 h with an average Coulombic efficiency of 99.92%, which is a record‐high reported value. Furthermore, the anode‐free full cell based on Au@Ti anode and expanded graphite cathode exhibits outstanding long‐term stability for 900 cycles with the capacity retention rate of 80%. This study provides an effective strategy to enhance the reversibility and utilization of the Al anode, which provides inspiration for advanced Al batteries. [ABSTRACT FROM AUTHOR]

In this work, Au–CuxOy hybrid nanoparticle-encapsulated hollow porous silica nanospheres (Au–CuxOy in HPSNs) were synthesized by immobilizing the catalytic functionality inside hollow cavities by using polyethyleneimine in a reverse microemulsion system as the void template as well as the platform to deliver the metals into the central voids. Compared with individual Au in HPSNs and CuxOy in HPSNs, the prepared Au–CuxOy in HPSNs demonstrate significantly improved catalytic efficiency for the reduction of various nitrophenols with NaBH4. At the molar ratio of 4-nitrophenol/Au of 30/1, the 4-nitrophenol conversions over Au–CuxOy in HPSNs reach 100% within 5.5 min, and catalytic efficiency is maintained during five cycles of catalytic reactions. The enhanced performance can be ascribed to the synergistic effect between Au and CuxOy, and the protection of silica shells to inner Au–CuxOy improve their catalytic stability. [ABSTRACT FROM AUTHOR]

Aqueous zinc-chlorine battery with high discharge voltage and attractive theoretical energy density is expected to become an important technology for large-scale energy storage. However, the practical application of Zn-Cl 2 batteries has been restricted due to the Cl 2 cathode with sluggish kinetics and low Coulombic efficiency (CE). Here, an aqueous Zn-Cl 2 battery using an inexpensive and effective MnO 2 redox adsorbent (referred to Zn-Cl 2 @MnO 2 battery) to modulate the electrochemical performance of the Cl 2 cathode is developed. Density functional theory calculations reveal that the existence of the intermediate state Cl ads free radical catalyzed by MnO 2 on the Cl 2 cathode contributes to the charge storage capacity, which is the key to modulate the electrode and improve the electrochemical performance. Further analysis of the Cl 2 cathode kinetics discloses the adsorption and catalytic roles of the MnO 2 redox adsorbent. The Zn-Cl 2 @MnO 2 battery displays an enhanced discharge voltage of 2.0 V at a current density of 2.5 mA cm -2 , and stable 1000 cycles with an average CE of 91.6%, much superior to the conventional Zn-Cl 2 battery with an average CE of only 66.8%. The regulation strategy to the Cl 2 cathode provides opportunities for the future development of aqueous Zn-Cl 2 batteries., (© 2023 Wiley‐VCH GmbH.)

Pd-Co x O y heteroaggregate-encapsulated hollow porous silica nanoreactors (Pd-Co x O y @HPSNs) were synthesized by a reverse microemulsion system. The key design of the developed reverse microemulsion system is to use poly(ethyleneimine) in the water droplets as the void templates for silica deposition and for anchoring the catalytic functionality inside the hollow silica nanospheres. The synthesized Pd-Co x O y @HPSNs contain ∼3 nm Pd-Co x O y hybrid nanostructures in ∼10 nm central cavities of silica nanospheres and illustrated a significantly promoted efficiency for hydrodechlorination of a series of chlorophenols into phenols under mild reaction conditions. The catalytic enhancement of Pd-Co x O y @HPSNs is ascribed to the synergistic effect between Pd and Co x O y and the protection of silica shells to the inner catalytic functionality.