Efficient Production\nof Graphene through a Partially\nFrozen Suspension Exfoliation Process: An Insight into the Enhanced\nInteraction Based on Solid–Solid Interfaces

Liquid\nphase exfoliation (LPE) offers a promising path\nfor scalable\ngraphene production, but struggles with high energy consumption and\nlow yield, with over 99.99% of the input energy wasted. Here, we present\nan energy-efficient approach for producing graphene via partially\nfrozen-suspension exfoliation (PFE). As opposed to traditional liquid–solid\ninterfaces, the solid–solid interface enhances shear strength\nbetween the frozen solvent and graphite from about 40 N m<sup>–2</sup> to 10<sup>5</sup> N m<sup>–2</sup>. Additionally, the suspension\nflow transitions from turbulent to laminar, aligning graphite parallel\nto the flow direction and conducive to the effective utilization of\n shear force. Compared to conventional liquid-phase exfoliation (LPE),\nPFE improves energy efficiency by 10<sup>2</sup>∼10<sup>3</sup> times. Furthermore, a production rate of 5 g h<sup>–1</sup> has been achieved in a 10 L tank at an ultralow shear rate of 3\n× 10<sup>2</sup> s<sup>–1</sup>.