化工学报
化工學報
화공학보
JOURNAL OF CHEMICAL INDUSY AND ENGINEERING (CHINA)
2015年
7期
2709-2717
,共9页
刘淑延%陈琦%吴彬%杨晓宁
劉淑延%陳琦%吳彬%楊曉寧
류숙연%진기%오빈%양효저
石墨烯%表面活性剂%吸附自组装%分散%分子模拟
石墨烯%錶麵活性劑%吸附自組裝%分散%分子模擬
석묵희%표면활성제%흡부자조장%분산%분자모의
graphenes%surfactants%adsorption self-assembly%dispersion%molecular simulation
采用分子动力学模拟分别研究了纯水和电解质溶液中 SDS 表面活性剂在纳米尺度石墨烯表面的自组装结构,考察了不同石墨烯层数对自组装吸附形态和SDS/石墨烯复合物悬浮密度的影响。模拟结果揭示了上述两种溶剂介质中,SDS的表面自组装结构形态与石墨烯的结构层数有关,增加石墨烯的层数能够加大吸附表面活性剂向溶液中的伸展程度,使表面活性剂自组装结构膨胀。此外电解质存在能够导致SDS表面活性剂在石墨烯表面吸附形态由多层结构向半圆胶束转化。模拟计算进一步发现SDS/石墨烯超分子复合物的悬浮密度随石墨烯层数的增加呈近似线性增加。
採用分子動力學模擬分彆研究瞭純水和電解質溶液中 SDS 錶麵活性劑在納米呎度石墨烯錶麵的自組裝結構,攷察瞭不同石墨烯層數對自組裝吸附形態和SDS/石墨烯複閤物懸浮密度的影響。模擬結果揭示瞭上述兩種溶劑介質中,SDS的錶麵自組裝結構形態與石墨烯的結構層數有關,增加石墨烯的層數能夠加大吸附錶麵活性劑嚮溶液中的伸展程度,使錶麵活性劑自組裝結構膨脹。此外電解質存在能夠導緻SDS錶麵活性劑在石墨烯錶麵吸附形態由多層結構嚮半圓膠束轉化。模擬計算進一步髮現SDS/石墨烯超分子複閤物的懸浮密度隨石墨烯層數的增加呈近似線性增加。
채용분자동역학모의분별연구료순수화전해질용액중 SDS 표면활성제재납미척도석묵희표면적자조장결구,고찰료불동석묵희층수대자조장흡부형태화SDS/석묵희복합물현부밀도적영향。모의결과게시료상술량충용제개질중,SDS적표면자조장결구형태여석묵희적결구층수유관,증가석묵희적층수능구가대흡부표면활성제향용액중적신전정도,사표면활성제자조장결구팽창。차외전해질존재능구도치SDS표면활성제재석묵희표면흡부형태유다층결구향반원효속전화。모의계산진일보발현SDS/석묵희초분자복합물적현부밀도수석묵희층수적증가정근사선성증가。
Molecular dynamics simulations were carried out to study the structure and morphology of SDS adsorbed on nano-sized graphene surfaces in pure water and electrolyte solution. The effects of the layer numbers of the graphene on the adsorption self-assembly structure and the buoyant density of the SDS/graphene assemblies were explored. The simulation results show that the aggregate morphology was highly dependent on the layer number of the graphene in both solutions. The stretching of surfactants to solution was enhanced with increasing layer number, leading to expansion of the self-assembly structure. In the presence of electrolyte in the solution, the surfactant micelles of SDS were transformed from the rough multi-layer to hemi-cylinder structure. In the meantime, the buoyant densities of the SDS/graphene assemblies were found to increase linearly with increasing layer number of the graphene. This behavior provided a direct theoretical basis for graphene dispersion with controlled thickness using the density gradient ultracentrifugation in the surfactant aqueous solution.