Eutectic cleavage of lignocellulosic biomass to incubate pseudo-graphitic carbon crystallites for high-efficiency sodium energy

Abstract

Lignocellulosic biomass represents a promising class of precursors for producing commercially viable hard carbons owing to its resource abundance, renewability, and sustainability. However, the compositional complexity makes it challenging to rationally regulate desired carbon microstructure for the use in sodium ion batteries. In this work, we propose a lignocellulosic cleavage strategy to incubate pseudographitic carbon crystallites at the molecule level by green eutectic chemistry. The molecular cleavage of cellulose, hemicellulose, and lignin promotes the construction of pseudographitic carbon crystallites having short, twisted, and expanded graphene interlayers as well as rich closed pores. The structurally favorable feature affords plentiful active sites and smooth ion diffusion channels for high-efficiency sodium energy storage. Impressively, the sodiation capacity is greatly increased to 326 mAh g -1 with an enhanced initial Coulombic efficiency of 85% and excellent rate/cycling performance.Advanced in situ/ex situ techniques are conducted to uncover the enhanced interface kinetics and underlying reaction mechanism. The present study underscores the importance of lignocellulosic cleavage method to achieve high-performance biomass-derived hard carbons for advanced sodium technology.