Efficient Production of Graphene through a Partially Frozen Suspension Exfoliation Process: An Insight into the Enhanced Interaction Based on Solid–Solid Interfaces
Kaixiang Pang, Xiaoke Fang, Chuanren Ye, Yuanhui Wang, Linlin Zhao, Chunhong Gong, Shuaishuai Zhou, Gai Zhao, Yanwu Zhu, Jingwei Zhang
Abstract
Liquid phase exfoliation (LPE) offers a promising path for scalable graphene production, but struggles with high energy consumption and low yield, with over 99.99% of the input energy wasted. Here, we present an energy-efficient approach for producing graphene via partially frozen-suspension exfoliation (PFE). As opposed to traditional liquid–solid interfaces, the solid–solid interface enhances shear strength between the frozen solvent and graphite from about 40 N m –2 to 10 5 N m –2 . Additionally, the suspension flow transitions from turbulent to laminar, aligning graphite parallel to the flow direction and conducive to the effective utilization of shear force. Compared to conventional liquid-phase exfoliation (LPE), PFE improves energy efficiency by 10 2 ∼10 3 times. Furthermore, a production rate of 5 g h –1 has been achieved in a 10 L tank at an ultralow shear rate of 3 × 10 2 s –1 .