Electrochemical performance of Fe x Mn 1−x -based metal–organic frameworks as electrode materials for supercapacitors

We use Fe as dopant in the metal–organic framework (MOF) of [(CH 3 ) 2 NH 2 ]Mn(HCOO) 3 , and four crystals were obtained with hydrothermal method according to the doping ratio: [(CH 3 ) 2 NH 2 ]Mn(HCOO) 3 , [(CH 3 ) 2 NH 2 ]Fe 0.1 Mn 0.9 (HCOO) 3 , [(CH 3 ) 2 NH 2 ]Fe 0.2 Mn 0.8 (HCOO) 3 and [(CH 3 ) 2 NH 2 ]Fe 0.3 Mn 0.7 (HCOO) 3 . And their electrochemical properties were studied by measuring cyclic voltammetry, galvanostatic charge–discharge and electrochemical impendence spectrum. The results showed that the sample of [(CH 3 ) 2 NH 2 ]Fe 0.1 Mn 0.9 (HCOO) 3 performed the highest specific electrical capacity of 167.95 F g −1 at a current density of 0.01 A g −1 . This work suggests that a small amount of Fe doping can improve the electrochemical performance of MOFs-based supercapacitors.