Khezri Bahareh, Beladi Mousavi Seyyed Mohsen, Sofer Zdeněk, Pumera Martin
Center for the Advanced Functional Nanorobots, Department of Inorganic Chemistry, University of Chemistry and Technology, Technická 5, Prague, Czech Republic.
Nanoscale. 2019 May 9;11(18):8825-8834. doi: 10.1039/c9nr02211b.
It has been more than a decade since nano/micromachines (NMMs) have received the particular attention of scientists in different research fields. They are able to convert chemical energy into mechanical motion in their surrounding environment. Herein, a powerful, efficient and fast strategy of using nanosized reduced graphene oxide flake (n-rGO)-based self-propelled tubular micromachines for the removal of nitroaromatic compounds (NACs) is described. This method relies on the integration of the rGO as a well-known adsorbent of aromatic compounds with chemically powered engines for the removal of explosive compounds such as 2,4,6-trinitrotoluene (TNT), 2,4,6-trinitrophenol (TNP) and 2,4-dinitrotoluene (DNT). Nanographene oxide reduced electrochemically inside the pores of the polycarbonate membrane to form an outer layer (n-rGO, adsorbent layer) of the micromachines. Subsequent electrodeposition of nickel (Ni, magnetic layer) and platinum (Pt, catalytic layer) resulted in the formation of n-rGO/Ni/Pt micromachines. Notably, the bubble-propelled micromachines were able to remove nitroaromatic compounds with high efficiency (∼90-92%) compared to the efficiency of magnetic-guided (22-42%) and static (2.5-7%) micromachines. Most importantly, the micromachines were regenerated and reused several times. The regeneration is based on an electrochemical method in which electron injection into the machine causes the expulsion of contaminants from the outer layer of the micromachines within a few seconds. The integration of the powerful self-propulsion, high adsorbent capacity of rGO and the introduced ultrafast regeneration procedure are beneficial for the realization of an active platform for water remediation.
纳米/微机器（NMMs）受到不同研究领域科学家的特别关注已有十多年了。它们能够在周围环境中将化学能转化为机械运动。在此，描述了一种使用基于纳米尺寸还原氧化石墨烯薄片（n-rGO）的自推进管状微机器去除硝基芳香族化合物（NACs）的强大、高效且快速的策略。该方法依赖于将作为芳香族化合物知名吸附剂的rGO与化学动力引擎相结合，以去除诸如2,4,6-三硝基甲苯（TNT）、2,4,6-三硝基苯酚（TNP）和2,4-二硝基甲苯（DNT）等爆炸性化合物。在聚碳酸酯膜的孔内进行电化学还原氧化石墨烯纳米片，形成微机器的外层（n-rGO，吸附层）。随后电沉积镍（Ni，磁性层）和铂（Pt，催化层），形成n-rGO/Ni/Pt微机器。值得注意的是，与磁导向微机器（22-42%）和静态微机器（2.5-7%）的效率相比，气泡驱动的微机器能够高效去除硝基芳香族化合物（约90-92%）。最重要的是，微机器可以再生并重复使用多次。再生基于一种电化学方法，其中向机器注入电子会在几秒钟内使污染物从微机器的外层排出。强大的自推进能力、rGO的高吸附容量以及引入的超快再生过程的整合，有利于实现一个用于水修复的活性平台。
