Confronted with severe electromagnetic wave pollution, the development of high-performance electromagnetic wave shielding or absorbing materials is an effective way to deal with it. Notably, double transition metal alloys and transition metal dichalcogenides have attracted extensive attention in electromagnetic wave absorption, but few reports have studied the effects of these two materials on electromagnetic wave absorption at the same time. In this work, cobalt-based alloy with magnetic loss mechanism was selected for composition optimization. The ternary metal-organic framework was prepared by the one-step method, and then CoCu/C was prepared by high temperature annealing. Finally, in the hydrothermal process, ultra-thin tungsten selenide nanosheets were coated on the surface of magnetic component, and the final polyhedral WSe₂/CoCu/C composites with multiple heterogeneous interfaces were obtained. The synergistic effect of dielectric and magnetic components optimizes impedance matching and allows more electromagnetic waves to enter the absorber. Subsequently, through the conduction loss of high conductivity graphitized carbon, interfacial polarization, and dipole polarization of heterogeneous interfaces between the components, the magnetic loss provided by CoCu alloy can work together to maximize the attenuation ability of electromagnetic waves. Exactly, the minimum reflection loss (RL_min) value of the composite reaches −53.43 dB when the matched thickness is 2.1 mm, while the maximum effective absorption bandwidth (EAB_max) reaches 6.0 GHz at a thin thickness of 1.8 mm. This work provides some support and reference for the design of novel electromagnetic wave absorbing materials via the dielectric/magnetic loss synergistic mechanism.

Aqueous zinc-ion batteries (AZIBs) have emerged as highly promising options for large-scale energy storage systems due to their cost-effectiveness, substantial energy capacity, and improved safety features. However, the Zn anode faces challenges such as self-corrosion and dendrite formation, which limit its practical use in AZIB applications. In this work, a simple blade-coating method was used to successfully coat poly (vinylidene fluoride–hexafluoro propylene) (PVDF-HFP) on the Zn anode. The coated Zn anode (P-Zn) displayed a stable cycling performance (700 h) at 1 mA cm⁻² current density in the symmetric cell. In addition, the full cell using MnO₂ as the cathode and P-Zn as the anode retained almost full capacity even after 1400 cycles at 2C, far outperforming the full cell using the unmodified Zn anode with only 50% capacity retention after 600 cycles. In situ optical observations of Zn deposition demonstrate that the special organic coating significantly enhances the uniform deposition of Zn²⁺, thus effectively mitigating corrosion and hydrogen evolution. Density Functional Theory (DFT) calculations show that the PVDF-HFP coating effectively narrows the adsorption energy gap between the P-Zn (002) and (101) planes, leading to the homogeneous deposition of Zn²⁺ with fewer Zn dendrites. A simple and feasible strategy for designing ultra-stable AZIBs by coating an organic protective layer on the Zn surface is provided by this work.