Bimetallic CoGa-LDH Integrated with Co-MOFs-Derived Co@C Nanosheets on Carbon Fiber for Flexible and High-Performance Potassium-Ion Supercapacitors

作者：Waqar ul Hasan, Mai Li, Wendong Xu, Zheyi Meng, Muhammad Zubair Nawaz, Jiale Wang, Chunrui Wang, Ping Zhong, Paul K. Chu · 发表于：ACS Applied Energy Materials · 年份：2024 · DOI：10.1021/acsaem.4c01733 · 被引用次数：24 · 研究领域：Supercapacitor Materials and Fabrication、MXene and MAX Phase Materials、Advancements in Battery Materials

Bimetallic layered double hydroxides (LDHs) have garnered significant attention from researchers due to their distinctive layered structure and compact ion channels for supercapacitor electrodes. Herein, a flower-like hierarchical nanostructure that combines flake-like cobalt gallium layered double hydroxide (CoGa-LDH) with a cobalt-metal–organic framework (Co-MOFs) derived carbon framework (Co@C) on carbon cloth (CoGa-LDH@Co@C) is designed to enhance the properties and functional diversity. The carbon nanolayer derived from calcination of the flake-like zeolite imidazolate framework-67 (ZIF-67) contains abundant Co nanoparticles that serve as nucleation sites for subsequent CoGa-LDH growth. This entails tight integration between the cobalt nanoparticles and CoGa-LDH, resulting in a unique nanoflower-like structure. Owing to the synergistic effects of the composite materials, the durability, conductivity, and surface area of the carbon-nanostructured skeleton, the electrochemical properties of LDH materials are improved significantly. CoGa-LDH@Co@C has exceptional electrochemical characteristics, such as a specific capacitance of 1180 F g –1 at a current of 0.25 mA cm –2 as well as 81.3% capacitance retention when the current is raised to 1 mA cm –2 . The asymmetric potassium-ion supercapacitor (ASC) assembled with CoGa-LDH@Co@C as the anode and activated carbon (AC) as the cathode exhibits an energy density of 45.02 W kg –1, power density of 753.46 W kg –1, and capacity rete...