The stability of graphene dispersions in water is of both scientific and technological significance. We studied the dispersion stability of electrochemically exfoliated graphene in an aqueous medium to minimize the strong aggregation tendency, within a short period, of graphene prepared in various electrolytes. This study focused on increasing the dispersion stability of graphene and finding the reason for its poor dispersion stability. The residual electrolyte trapped in the graphene layers was difficult to be removed from electrochemically exfoliated graphite and caused a significant aggregation. The stability and dispersion concentration can be improved by removing the trace amount of aqueous electrolyte. The aggregation mechanism of graphene in aqueous media is proposed and discussed in detail.

石墨烯分散体在水中的稳定性具有科学和技术意义。我们研究了电化学剥落的石墨烯在水性介质中的分散稳定性，以最大程度地减小短期内在各种电解质中制备的石墨烯的强聚集趋势。这项研究的重点是提高石墨烯的分散稳定性，并找出其分散稳定性差的原因。捕获在石墨烯层中的残留电解质很难从电化学剥离的石墨中去除，并导致明显的聚集。通过除去痕量的水性电解质可以提高稳定性和分散体浓度。提出并详细讨论了石墨烯在水性介质中的聚集机理。