Colloidal Motors 101: A Beginner's Guide to Colloidal Motor Research.

The research progress in colloidal motors, synthetic colloids that convert environmental energy and swim in water, has attracted much attention in recent years. Yet, its rapid development and interdisciplinary nature has created a hurdle for beginners, especially students and postdocs. In light of this challenge, this tutorial review gives a bird's eye overview of the research field of colloidal motors, presenting in a beginner-friendly manner subjects including the definition and significance of colloidal motors, physical challenges associated with their motion at the microscale, their fabrication and propulsion mechanisms, functionalities that enable their applications, and essential tools and techniques useful for beginners. Emphasis on each aspect is placed on elucidating and connecting important concepts and ideas, rather than on details and individual references. An appendix of recent review articles grouped by subjects on colloidal motors is given in the Supporting Information. This article equips beginners with a clear big picture and essential knowledge that will facilitate future explorations.