Graphene stirrer with designed movements: Targeting on environmental remediation and supercapacitor applications

Beyond the traditional focus on improvements in mechanical, electronic and absorption properties, controllability, actuation, and dynamic response of monoliths have received increasing attentions for practical applications. However, most of them could only realize simple response to constant conditions (e.g. a stationary magnetic field) while carrying out humdrum motions. By controlling distribution of metal organic framework obtained carbon-enriched Fe3O4 nanoparticles in self-assembly reduced graphene oxide (RGO) monoliths, we could achieve two distinctive RGO-Fe3O4 stirrers that could dynamically respond to the rapidly changing magnetic field while executing designed movements precisely: rotating with lying down posture or standing straight posture. These stirrers can not only be applied in environmental remediation (e.g. suction skimmer), but also be recycled as electrode active materials for supercapacitors after fulfilling their destiny, realizing transformation of trash to treasure, which will inspire other dynamically responsive monoliths for various applications. (C) 2017, Institute of Process Engineering, Chinese Academy of Sciences. Publishing services by Elsevier B.V.