Cobalt-Based\nLayered Metal–Organic Framework as an Ultrahigh Capacity Supercapacitor\nElectrode Material

Abstract

Metal–organic\nframeworks (MOFs) have recently received increasing interest due to\ntheir potential application in the energy storage and conversion field.\nHerein, cobalt-based layered MOF ({[Co­(Hmt)­(tfbdc)­(H₂O)₂]·(H₂O)₂}_<i>n</i>, Co–LMOF; Hmt = hexamethylenetetramine; H₂tfbdc = 2,3,5,6-tetrafluoroterephthalic acid) has been evaluated\nas an electrode material for supercapacitors. The Co–LMOF electrode\nexhibits a high specific capacitance and excellent cycling stability.\nIts maximum specific capacitance is 2474 F g^–1 at\na current density of 1 A g^–1, and the specific capacitance\nretention is about 94.3% after 2000 cycles. The excellent electrochemical\nproperty may be ascribed to the intrinsic nature of Co–LMOF,\nenough space available for the storage and diffusion of the electrolyte,\nand the particles of nanoscale size.