S10. XPS of high pressure exfoliated graphene from Graphene production by cracking

In recent years, graphene has found its use in numerous industrial applications due to its unique properties. While its impermeable and conductive nature can replace currently used anticorrosive toxic pigments in coating systems, due to its large strength to weight ratio, graphene can be an important component as a next-generation additive for automotive, aerospace and construction applications. The current bottlenecks in using graphene and graphene oxide and other two-dimensional materials are the availability of cost-effective, high-quality materials and their effective incorporation (functionalization and dispersion) into the product matrices. On overcoming these factors, graphene may attract significant demands in terms of volume consumption. Graphene can be produced on industrial scales and through cost-effective top-down routes such as chemical, electrochemical and/or high-pressure mechanical exfoliation. Graphene, depending on end applications, can be chemically tuned and modified via functionalization so that easy incorporation into product matrices is possible. This paper discusses different production methods and their impact on the quality of graphene produced in terms of energy input. Graphene with an average thickness below five layers was produced by both methods with varied defects. However, a higher yield of graphene with a lower number of layers was produced via the high-pressure exfoliation route.This article is part of a discussion meeting issue ‘A cracking approach to inventing new tough materials: fracture stranger than friction’.

近年来，石墨烯（graphene）凭借其独特的物理化学性能，已在众多工业场景中得到应用。其兼具阻隔性与导电性的特性，可替代涂料体系中目前使用的防腐有毒颜料；同时凭借优异的比强度，石墨烯可作为下一代添加剂，成为汽车、航空航天与建筑等应用领域的关键组分。当前制约石墨烯、氧化石墨烯（graphene oxide）及其他二维材料（two-dimensional materials）规模化应用的核心瓶颈，在于低成本且高品质的材料供给不足，以及如何将此类材料有效掺入（功能化与分散）至产品基体中。若能攻克上述难题，石墨烯或将在整体消费量层面迎来显著的市场需求。石墨烯可通过化学剥离、电化学剥离及/或高压机械剥离等低成本自上而下的工艺路线实现工业化规模生产。根据终端应用的具体需求，可通过功能化手段对石墨烯进行化学调控与改性，使其能够更便捷地掺入产品基体中。本文探讨了不同的石墨烯生产工艺，以及各工艺在能量投入维度对所制备石墨烯质量的影响。两类工艺均可制备平均层数低于五层的石墨烯，但会引入不同程度的结构缺陷；然而高压剥离工艺可获得层数更少、产率更高的石墨烯产品。本文属于专题讨论会议文集“研发新型强韧材料的突破性路径：超越摩擦的断裂机制”的一部分。