摘要
Given the layered crystal structure and tunable composition, ternary metal phosphorus trichalcogenides (MPCh <sub>3</sub> ) is an attractive anode material for potassium-ion batteries with higher surface activity and mobility than their binary analogues. However, how to improve the electronic conductivity, ion diffusion, and maintain high reversible potassiation/depotassiation processes are the main key issues for the development of MPCh <sub>3</sub> -based electrodes with high rate and long cycle life. For example, theoretically, FePSe <sub>3</sub> has a layered crystal structure with high electronic conductivity and low diffusion barrier, yet their K <sup>+</sup> -based electrochemical performance not well demonstrated. Here, we report a mechanical exfoliation method to prepare few-layer FePSe <sub>3</sub> -carbon nanotube (f-FePSe <sub>3</sub> /CNT) hybrids for use as high-efficiency K <sup>+</sup> storage anodes. Electrochemical performance, kinetic analysis, reaction mechanism analysis, and density functional theory calculations show that this strongly coupled 1D-2D hybrids promotes the reaction and diffusion of potassium ions, giving full play to the inherent advantages of materials with different dimensions. Therefore, the f-FePSe <sub>3</sub> /CNT PIB anodes exhibit high capacity (472.1 mA h g <sup>−1</sup> , 0.05 A/g), high rate (124.9 mA h g <sup>−1</sup> , 10 A/g), and cycling stability (>1000 cycles), which significantly exceeds the performance of its binary analogue, here FeSe. In addition, the full cells of potassium-ion battery and hybrid capacitor coupled with f-FePSe <sub>3</sub> /CNT anodes exhibit good cycling stability (500 cycles) and high energy/power density of 54.7 W h kg <sup>−1</sup> /5790.8 W kg <sup>−1</sup> , respectively, revealing its practical applications in a wide range of K <sup>+</sup> -based storage systems. We believe that this work will provide a universal strategy for effectively activating the K <sup>+</sup> electrochemical performance on a wide range of layered materials.