Facile Electrochemical Fabrication of Porous Fe2O3 Nanosheets for Flexible Asymmetric Supercapacitors

Fe 2 O 3 is one of the promising negative electrodes for asymmetric supercapacitors. But the rather low conductivity and poor cycling stability hinder its practical application. Herein, we report a facile electrochemical deposition technique to prepare porous Fe 2 O 3 nanosheets on carbon fabric (CF-Fe 2 O 3 ). The obtained Fe 2 O 3 displays highly porous nanosheet structure with reduced ion diffusion length and significantly enhanced conductivity. As a flexible supercapacitor electrode, the CF-Fe 2 O 3 hybrid electrode delivers a large areal capacitance of 1.56 F cm –2, good rate capability, and excellent cycling stability without capacitance decay after 5000 cycles. A packaged solid-state supercapacitor device based on the flexible CF-Fe 2 O 3 electrode exhibits an areal capacitance of 842 mF cm –2 and a volumetric energy density of 6.75 mWh cm –3, together with superior cycling performance which remains 93% capacitance after 4000 cycles. Moreover, the device performance is well retained under various bending and twisting states.