Data for: Shear-Induced Aggregation: The Achilles' Heel of High- Shear Mixing for Sustainable Graphene Production

The commercial production of pristine graphene at high yields remains a major challenge, limiting its widespread adoption across the range of applications for which it has been considered. Owing to its scalability, liquid-phase exfoliation using high-shear mixers is one of the most widely used techniques for large-scale graphene production in both industrial and academic settings. However, our findings reveal that shear-induced aggregation, an often-overlooked aspect of the high-shear mixing process, which intensifies by increasing the shear rate, drastically reduces the exfoliation yield for producing single- or few-layer graphene. Comparing high-shear mixing with ultrasonication as an alternative exfoliation method, we have found that the applied shear forces by high-shear mixers are markedly less efficient at peeling off individual graphene layers. Although high-shear mixing offers potential advantages in scalability, its poor energy efficiency renders it less viable for commercial production. Additionally, the graphene produced via high-shear mixing is of inferior quality in almost all aspects (e.g., flake size, defect density, and oxygen content) compared to that obtained through ultrasonication. These findings underscore the need to reevaluate high-shear mixing as a sustainable method for the production of single- and few-layered graphene.

高产量制备原始石墨烯（pristine graphene）仍是一项核心挑战，限制了其在各类预想应用场景中的大规模推广。得益于可规模化的优势，采用高剪切混合器（high-shear mixers）的液相剥离法（liquid-phase exfoliation）是目前工业与学术领域中大规模制备石墨烯最常用的技术之一。但我们的研究发现，高剪切混合过程中常被忽视的剪切诱导团聚（shear-induced aggregation）现象——其程度随剪切速率（shear rate）提升而加剧——会大幅降低单层或少层石墨烯（single- or few-layer graphene）的剥离产率（exfoliation yield）。将高剪切混合法与作为替代剥离方案的超声法（ultrasonication）进行对比后，我们发现高剪切混合器所施加的剪切力在剥离单片石墨烯薄片的效率上显著偏低。尽管高剪切混合法在规模化制备上具备潜在优势，但其能量效率低下的缺陷使其难以适配商业化量产需求。此外，与超声法制备的石墨烯相比，高剪切混合法得到的石墨烯在几乎所有性能指标上均表现更劣，例如薄片尺寸（flake size）、缺陷密度（defect density）与氧含量（oxygen content）。上述研究结果凸显了重新评估高剪切混合法作为单层、少层石墨烯可持续制备路径的必要性。