Carbon nanotubes-based anode materials for potassium ion batteries: A review

Potassium ion batteries (KIBs) are appealing candidates for new rechargeable batteries for large-grid electrochemical energy storage systems due to their substantial reserves and low cost. However, due to the large ionic size of K+, anode materials for KIBs have slow K+ ion reaction kinetics, substantial volume expansions, and an unstable solid electrolyte interface film, all of which can have a significant impact on the electrochemical properties of KIBs anodes. To create feasible KIBs anodes it is important to optimize both structural and electrochemical performance, which requires pragmatic structural design based on relevant materials. Carbon nanotubes (CNTs) has been attractive materials in the investigation as anode materials for KIBs due to their unique structural, mechanical, and electrical capabilities. This work reports the applications of CNTs in KIBs with their future development as electrically conductive framework materials in KIBs anodes. Various synthesis methods for the preparation of CNTs-based anodes for KIBs are addressed, which has shown remarkable morphological and electrochemical performance. Recent studies have focused on developing unique nanoarchitectures for KIB anodes to boost their capacity and lifetime. Moreover, to determine the differences, the electrochemical performances of CNTs-based anodes for LIBs and NIBs are compared to that of CNTs-based anodes for KIBs.