Rapid microwave reduction of electrochemically-derived graphene oxide for high-crystalline graphene membranes

Electrochemical oxidation of graphite has emerged as a sustainable and straightforward approach for the scalable synthesis of graphene oxide (GO). However, the reduction of electrochemically-derived GO (EGO) has received limited attention. Here, we present a rapid microwave reduction process specifically tailored for EGO, which exhibits distinct properties compared with chemically-derived GO (CGO). Unlike CGO membranes that require several minutes of microwave irradiation for reduction, EGO membranes can be transformed into high-crystalline graphene membranes (HCGM) in just 3 s, without pre-treatment or additional triggers. The resulting HCGM displays a significant aromatic domain size (∼100 nm), a high C/O atomic ratio (∼33), and impressive electrical conductivity (∼5 × 104 S m−1), surpassing previously reported microwave-reduced graphene. The remarkable efficiency of microwave reduction can be attributed to the unique molecular structure of EGO with abundant aromatic domains which enable efficient microwave absorption, inducing transient volumetric heating of EGO membranes. This study provides mechanistic insights into the microwave reduction process of GO and offers a facile and scalable pathway for HCGM production.[Figure not available: see fulltext.]. © 2023, Science China Press. 电化学氧化石墨, 可用于大规模合成氧化石墨烯, 是一种可持续 且直接的方法. 然而, 关于电化学衍生氧化石墨烯(EGO)进一步还原的 研究却很缺少. 本文中, 我们报道了EGO膜的快速微波还原过程. 化学 法合成的氧化石墨烯膜需要数分钟微波辐射才能被还原, 但是我们制 备的EGO膜经3秒微波辐射即可转化为高结晶石墨烯膜(HCGM), 并且 该过程无需对膜进行预处理或添加微波增敏剂. 与以前报道的微波法 制备的石墨烯相比, 本文制备的HCGM具有大尺寸芳香区(约 100 nm)、高碳/氧原子比(约33)和高电导率(约5 × 104 S m−1). EGO的 高微波还原效率可以归因于其独特分子结构, EGO中丰富的芳香区可 高效吸收微波, 引发EGO膜实现瞬时体相加热. 该研究加深了对氧化石 墨烯微波还原机理的理解, 并为HCGM的生产提供了一条便捷途径.