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Aqueous zinc ion batteries (AZIBs) are promising electrochemical energy storage devices due to their high theoretical specific capacity, low cost, and environmental friendliness. However, uncontrolled dendrite growth poses a serious threat to the reversibility of Zn plating/stripping, which impacts the stability of batteries. Therefore, controlling the disordered dendrite growth remains a considerable challenge in the development of AZIBs. Herein, a ZIF-8-derived ZnO/C/N composite (ZOCC) interface layer was constructed on the surface of the Zn anode. The homogeneous distribution of zincophilic ZnO and the N element in the ZOCC facilitates directional Zn deposition on the (002) crystal plane. Moreover, the conductive skeleton with a microporous structure accelerates Zn2+ transport kinetics, resulting in a reduction in polarization. As a result, the stability and electrochemical properties of AZIBs are improved. Specifically, the ZOCC@Zn symmetric cell sustains over 1150 h at 0.5 mA cm−2 with 0.25 mA h cm−2, while the ZOCC@Zn half-cell achieves an outstanding Coulombic efficiency of 99.79% over 2000 cycles. This work provides a simple and effective strategy for improving the lifespan of AZIBs. [ABSTRACT FROM AUTHOR]

Since the energy density and voltage window of supercapacitors cannot match that of lithium-ion batteries, supercapacitors are far from replacing batteries but can only be seen as a supplement to battery charge storage or transmission devices. The design of transition metal oxide-based electrodes with high cycling capacitance retention is very important for the development of supercapacitors. In this study, flower-like SAC@NiCoMn-LDH electrode materials with different Mn doping ratios were prepared by a hydrothermal method with mesoporous carbon (SAC) as the substrate. Density functional theory (DFT) calculations confirm that Mn doping can enhance the adsorption of OH− and the desorption of the H proton. In addition, Mn doping increases the density of states of LDH near the Fermi level and increases the number of active electrons, which is conducive to the occurrence of electrochemical reactions. In the three-electrode system, SAC@Ni2Co0.95Mn0.05-LDH with optimal doping ratio increased the specific capacitance by three times compared to that of NiCo-LDH and displayed an excellent cycling stability (83.76% capacitance retention after 50 000 cycles). Moreover, the prepared SAC@Ni2Co0.95Mn0.05-LDH and commercial activated carbon (AC) were made into electrode plates and then assembled into a SAC@Ni2Co0.95Mn0.05-LDH//AC asymmetric supercapacitor (ASC). The ASC exhibited high energy density (23.68 W h kg−1 at 325 W kg−1) and excellent specific capacitance retention (85.32% after 50 000 cycles), making it well suited for efficient wind energy storage and conversion with promising practical applications. [ABSTRACT FROM AUTHOR]

• CoP@FeP 2 heterostructure with different P vacancy concentrations were synthesized. • The diatomite structure was firstly introduced into the CoP@FeP 2 heterostructure. • The vacancy and hierarchical heterostructure facilitated the redox reaction kinetics. • The enhanced performance and energy storage mechanism of electrode were exhibited. Transition metal phosphide (TMP) is an attractive candidate for asymmetric supercapacitors (ASCs), but their low electric conductivity, limited redox active sites and sluggish charge transfer kinetics are still challenging. Herein, various phosphorus vacancy modified CP/FP heterostructures are successfully acquired via general three-step approach. Benefiting from their natural hierarchical heterostructure, these materials can access more active sites ions for redox reaction and boost their charge transfer kinetics. The formed phosphorus vacancy in lattice structure can provide plentiful lone pair electrons to facilitate electric conductivity. As a result, the pV-CP/FP2 electrode material achieves the best electrochemical performances, which delivers a specific capacitance (1028.8F/g at 5 mV s−1), outstanding rate capability and good cycling performance. Furthermore, the ASCs matched with pV-CP/FP2 and FeOOH electrode yields an exceptional cycling stability (85.7 % retention after 10,000 cycles), good Coulombic efficiency of 73.9 % from 1 to 8 A/g, a high energy density of 45.5 Wh kg−1 at a power density of 700 W kg−1, and as well maintains 36.0 Wh kg−1 at 5600 W kg−1. This work could supply original insights into the defect regulation and interfacial coupling of diatomite derivate heterojunctions for ASCs, and the Coscinodiscus-like pV-CP/FP2 electrode shows great potential for energy storage devices. [ABSTRACT FROM AUTHOR]