Island-like Ni–V–Fe Phosphide Heterostructures on Fe-Doped NiV-MOF Nanoflowers for Enhanced Supercapacitors
Yanqiu Xie, Haoze Wang, Carlos Garcia Nuñez, Xin Gao, Jiang Fan, Qian Li, He Bai, Fei Yao, Hongyan Yue
Abstract
Metal–organic frameworks (MOFs) and their derived heterostructures show significant potential in supercapacitors due to their unique electronic properties and interfacial effects. Here, Fe-doped NiV-MOF nanoflowers are synthesized on nickel foam (NF) via a solvothermal method, followed by in situ decoration of Ni–V–Fe phosphides (NiVFe-P) on the nanosheets to construct the island-like heterostructure (NiVFe-P@NiVFe-MOF/NF) through partial phosphorization. This island-like heterostructure possesses excellent electrical conductivity and adsorption performance, which are beneficial to enhance the rapid transfer efficiency of electrons/ions and the capability of charge storage. Therefore, NiVFe-P@NiVFe-MOF/NF delivers a high specific capacity (2319.3 C g –1 at 1 A g –1 ) and a remarkable stability (87.2% retention after 10,000 cycles). The assembled hybrid supercapacitor (NiVFe-P@NiVFe-MOF/NF//AC/NF) achieves an energy density of 109.4 Wh kg –1 at 1.16 kW kg –1 with an outstanding cycle life (93.4% retention after 10,000 cycles). This work highlights the potential of island-like heterostructures as a promising strategy for developing advanced supercapacitor electrodes.