A hexaazatriphenylene-based polymer as high performance anode for Li-/Na-/K-ion batteries

Organic electrodes have attracted a lot of attention in alkali metal-ion batteries recently due to their flexibility, potentially low cost, and environmental benignity compared to traditional inorganic materials. Even though alkali metal-ion batteries are supposed to be alike, the application of one organic electrode in different batteries was rarely reported and systematically investigated. Here, we report a hexaazatriphenylene-based polymer (HAT-PPDA) as anodes for Li-/Na-/K-ion batteries. The results showed that every hexaazatriphenylene imide unit could accept 6 electrons for Na- (SIBs) and K-ion batteries (PIBs); while it could accept 3 more electrons for Li-ion batteries (LIBs), yielding high reversible capacities of 405 mAh g−1 in PIBs, 397 mAh g−1 in SIBs and 681 mAh g−1 in LIBs at 100 mA g−1, respectively. Particularly, the performance of HAT-PPDA was superior to the previously reported organic anodes for PIBs. On the other hand, the rate performance of HAT-PPDA in SIBs was better than those in PIBs and LIBs. This work provides universal high performance anodes for Li-/Na-/K-ion batteries, reveals insights into the charge storage of organic electrodes in alkali metal-ion batteries and will guide the future development of organic materials for achieving high performance batteries.