No abstract

For obtaining high-performance lithium-ion batteries, it is an important route to develop new cathode material with high capacity. Herein, a one-dimensional coordination polymer [Co(4-DTBPT) (DMF)2(H2O)2] (4-DTBPT) (C10H4O8) (Co-DTBPT) (4-DTBPT =...

It is a considerably attractive task to search for new high-performance electrode materials for supercapacitors from pristine coordination polymers. Herein, a one-dimensional (1D) Cu-based coordination polymer ([Cu­(BGPD)­(DMF)2(H2O)], Cu-BGPD; BGPD = N,N′-bis­(glycinyl)­pyromellitic diimide; DMF = dimethylformamide) has been synthesized. When utilized as the electrode material for supercapacitors, in a three-electrode system, the Cu-BGPD electrode delivers a high specific capacitance of 1530 F g–1 (corresponding to a specific capacity of 213 mAh g–1) at 1 A g–1 with a capacitance retention of 95.9% after 2000 cycles at 1 A g–1. Impressively, the asymmetric supercapacitor comprising Cu-BGPD as the positive electrode and the rGO as the negative electrode delivers the maximum energy density of 15.25 Wh kg–1 at a power density of 0.85 kW kg–1. Our research shows that it is also a practical way to develop new high-performance electrode materials of supercapacitors from 1D coordination polymers.

The capacity of cathode materials is one of the main factors to limit the performance of lithium-ion batteries (LIBs), so it is urgent to develop high-performance cathode materials. Herein, trinitrohexaazatrinaphthalene (TNHATN) including an electron-withdrawing group (nitro, -NO2) was synthesized by the condensation reaction between hexaketocyclohexane and 4-nitro-o-phenylenediamine, and it was first investigated as a cathode material for lithium-ion batteries. The TNHATN electrode displays a high discharge specific capacity of 361.7 mAh g-1 at 0.05 A g-1 and a superior cycling stability, remaining the capacity retention of 97.9 % after 200 cycles. The excellent behaviors may be ascribed to its π-conjugated structure including electron-withdrawing groups and multiple redox active sites. The experimental resultes reveal the redox active sites are pyrazine nitrogen atoms and oxygen atoms from nitrio groups. This work confirms that it is an effective route to introduce an electron-withdrawing group into a π-conjugated compound for obtaining high-performance organic cathode materials of LIBs.