Nitrogen-Linked Hexaazatrinaphthylene Polymer as Cathode Material in Lithium-Ion Battery

Nitrogen-linked hexaazatrinaphthylene polymer (N² -HATN) as organic cathode material with low HOMO-LOMO gap was synthesized and was observed to possess reversible high capacity and unexpected long-term cycling stability. The pre-treated N² -HATN and pRGO combination demonstrated good structure compatibility and the resultant cathode exhibited a constant increment of capacity during the redox cycles. The initial capacity at 0.05 A g^-1 was 406 mA h^-1  g^-1 , and increased to 630 mA h^-1  g^-1 after 70 cycles. At 0.5 A g^-1 discharging rate, the capacity increased from an initial value of 186 mA h^-1  g^-1 to 588 mA h^-1  g^-1 after 1600 cycles. The pseudocapacitance-type behavior is postulated to be attributed to the structure compatibility between the active material and pRGO.