A template oriented one-dimensional Schiff-base polymer: towards flexible nitrogen-enriched carbonaceous electrodes with ultrahigh electrochemical capacity.

Lithium-ion capacitors (LICs) have attracted much attention considering their efficient combination of high energy density and high-power density. However, to meet the increasing requirements of energy storage devices and the flexible portable electronic equipment, it is still challengable to develop flexible LIC anodes with high specific capacity and excellent rate capability. Herein, we propose a delicate bottom-up strategy to integrate unique Schiff-base-type polymers into desirable one-dimensional (1D) polymeric structures. A secondary-polymerization-induced template-oriented synthesis approach realizes the 1D integration of Schiff-base porous organic polymers with appealing characteristics of high nitrogen-doping level and developed pore channels, and a further thermalization yields the flexible nitrogen-enriched carbon nanofibers with high specific capacity and fast ion transport. Remarkably, when used as the flexible anode in LIC, the NPCNF//AC LIC demonstrates a high energy density of 154 Wh kg−1 at 500 W kg−1 and a high-power density of 12.5 kW kg−1 at 104 Wh kg−1. This work may provide a new scenario for synthetizing 1D Schiff-base-type polymer derived nitrogen-enriched carbonaceous materials towards promising free-standing anode in LICs.