Carbon intermediate boosted Fe–ZIF derived α –Fe 2 O 3 as a high-performance negative electrode for supercapacitors

Earth-abundant Fe 2 O 3 is a promising material for the negative electrode of supercapacitors by virtue of its wide potential windows. However, the unsatisfactory electrical conductivity and poor ionic diffusion rate within Fe 2 O 3 results in degraded electrochemical performance. In this work, to address these issues, we demonstrate an easy method to synthesize Fe-based zeolitic imidazolate framework (Fe–ZIF) derived α –Fe 2 O 3 @C with remarkable supercapacitive properties. The as-obtained α –Fe 2 O 3 @C electrode, with the particular benefit of dispersed distribution of carbon, enabling fast electrochemical response, presents a prospective specific capacitance of 161 Fg −1 at a current density of 1 Ag −1 . Furthermore, by using the α –Fe 2 O 3 @C architecture as the negative electrode, we fabricated a supercapacitor with Na 0.5 MnO 2 as the positive electrode. Our supercapacitor shows a high energy density of 25 Whkg −1 , while the corresponding power density is 2400 Wkg −1 at a current density of 2 Ag −1 .