Laboratory for Advanced Carbon Nanomaterials , Kazan Federal University , Kremlyovskaya Street 18 , Kazan 420008 , Russian Federation.
ACS Appl Mater Interfaces. 2018 Nov 21;10(46):40024-40031. doi: 10.1021/acsami.8b15129. Epub 2018 Nov 8.
Graphene oxide (GO) aqueous solutions are known to form liquid crystals that can switch in electric fields. Magnetic fields as external stimuli are inefficient toward GO because of its diamagnetic properties, and GO is known to be insoluble in most of the organic solvents. In this study, composites of GO with oleate-protected magnetite nanoparticles were prepared as stable colloid solutions in the mixed isopropanol-chloroform solvents. The structure of the composite particles and the optical properties of their solutions can be controlled by the ratio of the mixing parent components. The as-prepared solutions are highly responsive to external magnetic field. As the consequence, the optical transmission and the direction of light scattering can be efficiently manipulated. These systems pave the way for fabricating functional materials, such as magneto-optical switches, density-gradient materials, and micromotors. Solubility in nonpolar organic solvents broadens the scope of their potential applications.
氧化石墨烯（GO）水溶液已知可形成液晶，可在电场中切换。由于其反磁性，磁场作为外部刺激对 GO 效率不高，并且已知 GO 不溶于大多数有机溶剂。在这项研究中，制备了油酸盐保护的磁铁矿纳米粒子与 GO 的复合材料，在异丙醇-氯仿混合溶剂中作为稳定的胶体溶液。复合粒子的结构和溶液的光学性质可以通过混合母体成分的比例来控制。所制备的溶液对外磁场具有高度响应性。因此，可以有效地操纵光传输和光散射的方向。这些系统为制造功能材料铺平了道路，例如磁光开关、密度梯度材料和微马达。在非极性有机溶剂中的溶解度拓宽了它们潜在应用的范围。
