High-pressure-triggered homodisperse reconstruction of graphene nanosheets for Na ion storage

Abstract

By precisely adjusting the interlayer spacing and pore structure (including porosity, pore size, pore size distribution, and pore morphology) of graphene, it has been demonstrated that the specific energy of sodium-ion batteries can be enhanced. However, due to the intricate synergistic effect between electrolytes and electrode materials during electrochemical processes, there is currently insufficient evidence to elucidate their respective contributions to storage performance. Here, we employed a microfluidization strategy to construct graphene with different interlayer spacings and after reduction, different pores with wrinkles are formed during the removal of oxygen functional groups. Our method can effectively adjust interlayer spacing and control the pore structure of graphene clusters. Furthermore, employing scanning electrochemical microscopy (SECM) to detect the interfacial electron transport rate of graphene revealed the inherent kinetic features of the interlayer spacing and pore structure. The appropriate interlayer spacing, which serves as a crucial prerequisite for Na ion insertion/extraction, in conjunction with the abundant pore structure, contributes to an exceptional electron transport rate. Highlighting the synergistic effect of interlayer spacing, the porous structure plays a pivotal role in governing the rate of electron transport.