合成与生物胶体教育部重点实验室 江南大学化学与材料工程学院，江苏 无锡 214122
以离子液体（IL-NH2）对氧化石墨烯进行修饰，制备得到离子液体修饰的还原氧化石墨烯（rGO-IL），将其作为颗粒乳化剂稳定含有苯胺单体的油相，制备稳定均匀的Pickering乳液，然后通过引发苯胺单体聚合得到石墨烯/聚苯胺空心微球。离子液体的引入不仅可以调节Pickering乳化剂的润湿性，还能避免降低材料的电导率。通过调节IL-NH2对石墨烯的修饰程度调节了rGO-IL的润湿性，并探究了rGO-IL的润湿性、浓度以及乳化时的油水比对Pickering乳液性质的影响。利用超景深三维显微镜观察了rGO-IL稳定的Pickering乳液状态；利用傅里叶红外光谱仪、拉曼光谱仪和扫描电子显微镜对所得石墨烯/聚苯胺空心微球的化学结构和形貌进行了观察；利用循环伏安法与恒流充放电法对空心微球的电容性能进行了探究。结果显示，石墨烯/聚苯胺空心微球比电容可以达到451.8 F/g，是二维石墨烯/聚苯胺材料的近两倍(227 F/g)；另外空心微球表现出良好的倍率性能，当电流密度从0.5 A/g增加至10 A/g时，其电容保持率高达92.4%，远高于二维材料的46.5%。
A kind of graphene/polyaniline hybrid hollow capsules has been fabricated via Pickering emulsion using ionic liquid-modified reduced graphene oxide (rGO-IL) Pickering emulsifier. In our strategy, rGO-IL was first prepared and employed to stabilize the oil phase containing aniline to prepare stable and uniform Pickering emulsion. Upon the polymerization of aniline at the oil/water interface, ionic liquid functionalized graphene/polyaniline hollow spheres (rGO-IL/PANI HS) was obtained. The functionalization of rGO by ionic liquid can not only adjust the wettability of rGO, but also avoid reducing its conductivity. The wettability of rGO-IL was adjusted by adjusting modification degree of graphene by IL-NH2. The influence of wettability and concentration of rGO-IL as well as oil-water ratio on the properties of Pickering emulsion was explored. At the same time, the effect of aniline addition on the electrochemical performance of rGO-IL/PANI HS was also studied. The Pickering emulsions stablized by rGO-IL were observed by super deep scene 3D microscope. According to the emulsion droplet morphology and particle size distribution, the optimal preparation conditions were obtained. The chemical structure and morphology of rGO-IL/PANI HS were analyzed by FT-IR, Raman spectrum and scanning electron microscope. The results showed that the final product prepared from the rGO-IL-stabilized Pickering emulsion has a spherical shape, and an obvious hollow structure could be observed from the breakage. The capacitance performance of rGO-IL/PANI HS was explored by cyclic voltammetry and galvanostatic charge-discharge. The specific capacitance of rGO-IL/PANI HS was able to reach a maximum of 451.8 F/g, which was nearly double that of two-dimensional rGO-IL/PANI materials (227 F/g). In addition, the prepared rGO-IL/PANI HS also showed excellent rate performance. When the current density was increased from 0.5 A/g to 10 A/g, the capacitance retention rate of rGO-IL/PANI HS was as high as 92.4%, much higher than 46.5% of two-dimensional materials.