A stable Ni-based coordination polymer used as anode materials for supercapacitors

Abstract Owing to their porosity and large surface area, coordination polymers (CPs) have received widespread attention in the potential application of electrode materials. Herein, a new Ni (II) CP, namely, {[Ni(TPTA)0.5(1,4-bib)0.5(H2O)2]·CH3OH}n (1), has been synthesized with the help of Ni(NO3)2, 2′-amino-[1,1′:4′,1″-terphenyl]-3,3″,5,5″-tetracarboxylic acid (H4TPTA) and 1,4-bis(1-imidazoly)benzene (1,4-bib) under solvothermal methods. The electrochemical performances of CP 1 modified foam nickel (NF) electrodes were measured. When the current density (J) was 0.5 ​A ​g−1, the specific capacitance (C) of CP 1@NF electrode was 227.1 ​F ​g−1, whose capacitance retention rate was 90.8% of the original one after 2000 cycles. In addition, an asymmetric supercapacitor (ASC) was assembled in 1 ​M KOH electrolyte, in which CP 1@NF and AC were used as the anode and cathode, respectively. The capacitance of ASC still retained 90% of the original one after 2000 cycles at a current density of 0.5 ​A ​g−1. And it exhibited the energy density (E) of 8.36 ​Wh kg−1 when the power density (P) was 501.3 ​W ​kg−1.