High solubility in aprotic organic electrolytes and poor electrical conductivity are the main restrictions of organic electrodes in practical application. Conductive binder contributes to the high-performance electrodes as it enables both mechanical and electronic integrity of the electrode, which have been scarcely explored for organic electrodes. Herein, a conductive interpenetrating polymeric network is synthesized through in situ polymerization of polyaniline with poly­(acrylic acid) (denoted PAA-PANi), which served as a novel conductive binder for organic 2-aminoanthraquinone (AAQ) materials. The conductive PANi component enhances the electrical conductivity of the electrode. Meanwhile, the PAA component serves as the binding matrix to condense with the amino groups (−NH2) of AAQ, which therefore effectively inhibits their dissolution and maintains electrode integrity during cycling. As expected, the conductive binder exhibits both excellent electrical conductivity (10–3 S cm–1) and strong mechanical adhesion. The AAQ/reduced graphene oxide (AAQ@rGO) composite electrode prepared with the as-synthesized PAA-PANi binder delivers a high specific capacity of 126.1 mAh g–1 at 0.1 A g–1, superior rate capability (71.3 mAh g –1 at 3 A g–1), and outstanding cycling stability (2000 cycles at 1 A g–1), which greatly rivals polyvinylidene fluoride and PAA binder-based electrodes. Such a strategy points the way for the design and synthesis of conductive polymeric binders for organic electrodes, whose electrical conductivity and dissolution are massive issues.

Potassium-ion batteries (PIBs) as a new electrochemical energy storage system have been considered as a desirable candidate in the post-lithium-ion battery era. Nevertheless, the study on this realm is in its infancy; it is urgent to develop electrode materials with high electrochemical performance and low cost. Iron sulfides as anode materials have aroused wide attention by virtue of their merits of high theoretical capacities, environmental benignity, and cost competitiveness. Herein, we constructed carbon-free crystal-like Fe 1−x S and demonstrated its feasibility as a PIB anode. The unique structural feature endows the prepared Fe 1−x S with plentiful active sites for electrochemical reactions and short transmission pathways for ions/electrons. The Fe 1−x S electrode retained capacities of 420.8 mAh g −1 after 100 cycles at 0.1 A g −1 and 212.9 mAh g −1 after 250 cycles at 1.0 A g −1 . Even at a high rate of 5.0 A g −1 , an average capacity of 167.6 mAh g −1 was achieved. In addition, a potassium-ion full cell is assembled by employing Fe 1−x S as an anode and potassium Prussian blue as a cathode; it delivered a discharge capacity of 127.6 mAh g −1 at 100 mA g −1 after 50 cycles.

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