Nanocarbon applications in anode-free batteries

Anode-free batteries (AFBs), distinguished by the absence of a prefabricated anode, present a promising avenue for achieving higher energy densities and simplified manufacturing in energy storage systems. This review comprehensively explores the pivotal role of nanocarbons in enabling the successful implementation of AFBs across various battery chemistries, including Li-, Na-, K-, Al-, Zn-metal batteries, and Li-S, Na-S batteries, as well as Zn-air, Zn-MnO 2 , Na–CO 2 batteries. The diverse allotropes of carbon, ranging from 1D (carbon nanotubes, CNTs, and carbon nanofibers, CNFs), 2D (graphene and its derivatives) 3D (carbon cloth, carbon paper, etc.) structures, exhibit unique properties that can be used to address key challenges such as dendrite growth and unstable solid electrolyte interphase formation in AFBs. The multifaceted applications of nanocarbon in AFBs, encompassing protective coatings on current collectors, free-standing electrodes, separator modifications, and cathode enhancements will be discussed. The concept of metalphilicity, which is important for controlling metal deposition and preventing dendrite formation, is also discussed. This perspective provides a comprehensive framework for discussing the application of nanocarbon materials in AFBs, covering their roles, mechanisms, recent developments, challenges, and future perspectives.