Constructing Carbon Nanobubbles with Boron Doping as Advanced Anode for Realizing Unprecedently Ultrafast Potassium Ion Storage

Carbonaceous material with favorable K+ intercalation feature is considered as a compelling anode for potassium-ion batteries (PIBs). However, the inferior rate performance and cycling stability impede their large-scale application. Here, facile template method utilized to synthesize boron doping carbon nanobubbles (BCNBs). The incorporation of into structure introduces abundant defective sites improves conductivity, facilitating both intercalation-controlled capacitive-controlled capacities. Moreover, theoretical calculation proves that can effectively improve conductivity facilitate electrochemical reversibility in PIBs. Correspondingly, designed BCNBs delivers high specific capacity (464 mAh g−1 at 0.05 A g−1) an extraordinary (85.7 50 g−1), retains considerable retention (95.2% relative 100th charge after 2000 cycles). Besides, strategy pre-forming stable artificial inorganic solid electrolyte interface realizes initial coulombic efficiency 79.0% BCNBs. Impressively, dual-carbon capacitor coupling displays energy density (177.8 Wh kg−1). This work not only shows great potential utilizing heteroatom-doping boost potassium ion storage but also paves way designing high-energy/power devices.