Polyperylenediimide (PDI) is always subject to its modest conductivities, limited reversible active sites and inferior stability for potassium storage. To address these issues, herein, we firstly propose an organic-inorganic hybrid (PDI@Fe-Sn@N-Ti3 C2 Tx ), where Fe/Sn single atoms are bound to the N-doped MXenes (N-Ti3 C2 Tx ) via the unsaturated Fe/Sn-N3 bonds, and functionalized with PDI via d-π hybridization, forming a high conjugated δ skeleton. The resulted hybrid cathode endowed with enhanced electronic/ionic conductivities, lowered dissociation barriers of multiple redox centers and a stable cathode electrolyte interphase layer displays a 14-electron involved high-rate capacities and long cycle life. Moreover, it shows competitive performance in full cells even under different folding states and low operating temperatures.
Keywords: Fe/Sn single atoms; N-doped MXenes; organic-inorganic hybrid; polyperylenediimide cathode; potassium-ion batteries.
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