▎ 摘　　要

Recent work has revealed that the lateral size of graphene quantum dots (GQDs) is a crucial factor dictating their biomedical applications. A facile method to sort as-prepared GQDs with wide size distributions into different sized GQDs with narrow size distributions by using aluminum ions was developed. The mechanism of this separation was investigated. The obtained differently sized GQDs were found to exhibit dissimilar cytotoxicity, which suggests that their effects on cells or organisms could be different.