Central Advanced Research & Engineering Institute, Hyundai Motor Company , Uiwang 16082, Korea.
ACS Appl Mater Interfaces. 2016 Aug 24;8(33):21595-602. doi: 10.1021/acsami.6b07272. Epub 2016 Aug 15.
Aggregation is a critical limitation for the practical application of graphene-based materials. Herein, we report that graphene oxide (GO) nanosheets chemically modified with ethanolamine (EA), ethylene glycol (EG), and sulfanilic acid (SA) demonstrate superior dispersion stability in organic solvents, specifically EG, based on the differences in their covalent chemistries. Functionalized GO was successfully dispersed in EG at a concentration of 9.0 mg mL(-1) (0.50 vol %), the highest dispersion concentration reported to date. Moreover, our study introduces a unique analytical method for the assessment of dispersion stability and successfully quantifies the instability index based on transmission profiles under centrifugation cycles. Interestingly, GO-EG and GO-EA exhibited highly improved dispersion stabilities approximately 96 and 48 times greater than that of GO in EG solvent, respectively. This finding highlights the critical role of surface functional groups in the enhancement of chemical affinity and miscibility in the surrounding media. We anticipate that the novel structural designs and unique tools presented in this study will further the understanding and application of chemically functionalized carbon materials.
聚集是限制石墨烯基材料实际应用的一个关键因素。在此，我们报告称，通过乙醇胺（EA）、乙二醇（EG）和磺胺酸（SA）对氧化石墨烯（GO）纳米片进行化学修饰，根据它们的共价化学性质的不同，GO 纳米片在有机溶剂，特别是 EG 中表现出优异的分散稳定性。功能化 GO 可成功分散在 EG 中，浓度为 9.0mg/mL（0.50vol%），这是迄今为止报道的最高分散浓度。此外，我们的研究引入了一种独特的分析方法来评估分散稳定性，并成功地根据离心循环下的透射谱量化了不稳定性指数。有趣的是，GO-EG 和 GO-EA 在 EG 溶剂中的分散稳定性分别比 GO 提高了约 96 倍和 48 倍。这一发现突出了表面官能团在增强周围介质中的化学亲和力和混溶性方面的关键作用。我们预计，本研究提出的新颖结构设计和独特工具将进一步加深对化学功能化碳材料的理解和应用。
