Self-Propelled Micro-/Nanomotors of ZnO Nanoshuttles Induced by Surface Defects

Abstract

To accomplish various complex tasks in the microworld, micro-/nanomotors (MNMs) with diverse swimming characteristics have attracted more and more attention. In this work, ZnO nanoshuttles were synthesized by a simple hydrothermal method. In addition, MNMs based on ZnO nanoshuttles have been designed, exhibiting self-propelled swimming characteristics with three motion modes of shake, rotation, and translation in water. It is revealed that the asymmetrically distributed defects on the surface of ZnO nanoshuttles are responsible for the swimming modes. The unique shuttle-like structure helps to reduce the drag in a low Reynolds number environment and endows the selfpropelled ZnO nanoshuttle motor with a relatively high swimming velocity (5.16 μm/s). In addition, to demonstrate the versatility and openness of ZnO nanoshuttle MNMs, ZnO/Co magnetic MNMs and ZnO/TiO 2 Janus MNMs were prepared by simple Co doping and TiO 2 coating, respectively. This study reveals the possible role of surface defects in regulating the motion behavior of ZnO-based MNMs and also provides a feasible low-cost method for the large-scale fabrication of self-asymmetric fuel-free micro-/nanomotors.

Light-Switchable Biocatalytic Covalent–Organic Framework Nanomotors for Aqueous Contaminants Removal

“…Self-propelled nanomotors, with their ability to autonomously navigate and perform specific tasks on the nanoscale, have emerged as a fascinating area of research in recent years. These nanoscale devices harness various propulsion mechanisms, such as chemical reactions, − light, − magnetic field, and ultrasound, to generate motion. Self-propelled nanomotors offer unique advantages in addressing unmet challenges in biomedicine and the environment, showing great promise in targeted drug delivery, , sensing, , and environmental remediation, − where their self-propulsion capabilities and small size (100 nm to 1 μm) enable them to actively navigate through complex biological or environmental matrices.…”