Anchoring Multi‐Coordinated Bismuth Metal Atom Sites on Honeycomb‐Like Carbon Rods Achieving Advanced Potassium Storage

Abstract

AbstractCarbonaceous materials are recognized for their high conductivity and adaptable structures, making them potential candidates for potassium‐ion batteries (PIBs). Yet, their application has been restricted due to challenges like limited potassium storage and slow kinetics. Addressing these issues, this study presents a novel method by anchoring nitrogen‐oxygen‐coordinated bismuth metal atom sites onto honeycomb‐like carbon rods, termed Bi‐N4‐O2@HCR. This aims to enhance PIB performance by exploiting carbonaceous materials' strengths and mitigating their limitations. Through comprehensive experiments and theoretical simulations, it is found that Bi‐N4‐O2 sites enrich potassium storage and facilitate potassium ion migration, thus improving transport efficiency and reaction kinetics. The resulting anode showcased rapid and durable potassium storage, with a remarkable capacity of 190.7 mAh g−1 at 30 A g−1 and maintaining 192.2 mAh g−1 over 4200 cycles at 5 A g−1, outperforming many existing carbon anodes. Additionally, in full cell tests, it exhibited excellent rate performance and ultra‐long cycle life, sustaining up to 8000 cycles with a stable capacity of 88.9 mAh g−1 at 5 A g−1. This research underscores the significance of incorporating unique metal sites on carbon substrates to advance battery technology.