Self-Propelled Activated Carbon Micromotors for “On-the-Fly” Capture of Nitroaromatic Explosives

Abstract

Usage of nitroaromatic compounds (NACs) for industrial or military purposes leads to serious concern because of their detrimental effects on human health when they leak to groundwater. Among different ways to remove NACs from water sources, adsorption has been considered as an environmentally safe method. However, diffusion-limited characteristics of the adsorption method increase the time required to remove NACs. In this study, we utilize biocompatible and low-cost activated carbon (AC) as self-propelled micromotors for “on-the-fly” capture of 2,4,6-trinitrophenol (picric acid). The micromotors effectively capture picric acid with their intrinsic movement capabilities and demonstrate effective decrease in the adsorption time. The results highlight that even a well-known adsorbent material, AC, can be further improved via “on-the-fly” adsorption capability of micromotors.

Hybrid Enzymatic/Photocatalytic Degradation of Antibiotics via Morphologically Programmable Light‐Driven ZnO Microrobots

“…The motion of ZnO‐Au microrobots leads to a higher mass transfer in the solution, which significantly enhances OTC adsorption and degradation. [ 42–44 ] The experiments conducted with nonmotile ZnO particles (Figure S12, Supporting Information) support this claim by demonstrating a lower OTC removal capacity than motile ZnO‐Au microrobots. Moreover, the control experiments (Figure S13, Supporting Information) highlight that OTC removal mechanisms observed in laccase‐immobilized ZnO‐Au microrobots can be further improved by precisely adjusting pH and temperature of OTC solutions.…”

Shape-Controlled Self-Assembly of Light-Powered Microrobots into Ordered Microchains for Cells Transport and Water Remediation

“…Artificial micro/nanorobots, a relatively young field of research that has seen significant growth, becoming one of the most attractive research topics nowadays, are autonomously self-propelled micro/nanomaterials able to harvest and convert energy from their surrounding environment into autonomous movement with distinct capabilities for accomplishing various tasks. − Various energy sources, including chemical fuels (H 2 O 2 , glucose, urea) or external stimuli such as light, magnetic fields, and ultrasound, have been exploited to activate the self-propulsion of micro/nanorobots. − Particularly, light is a very attractive energy source to power microrobots because it is powerful, renewable, and abundant. To obtain an active moving particle, it is necessary to have an asymmetric structure, which in turn converts this asymmetry into motion. , In this regard, the “two-faced” Janus microrobots consisting of a photocatalytic semiconductor (UV-light-activated TiO 2 and ZnO, visible light-activated Fe 2 O 3 and BiOI) asymmetrically covered by a metal layer (Pt, Au, Ag) represent the most efficient light-powered self-motile microrobots. − Owing to their powerful motion, micro/nanorobots can accomplish numerous and different tasks, holding excellent prospects in various application fields from biomedicine to environmental remediation and sensing. − Still, further improvements are expected from rudimentary communication between individual microrobots (e.g., micro/nanorobotic swarms), allowing synchronized operation and high adaptability to different complex conditions. − On the basis of this consideration, the careful selection of the constituent materials plays a crucial role in micro/nanorobots’ organization manners.…”

Light‐Propelled Nanorobots for Facial Titanium Implants Biofilms Removal

“…They are autonomous machines at the small scale that can be propelled converting several energy sources such as chemical fuels, magnetic field, acoustic field, and light into mechanical energy. [11][12][13][14][15][16][17] Selfpropelled nanorobots are aimed to succeed where conventional nanomedicine fails. For example, micro-and nanorobots can provide real-time diseases detection, [18,19] monitoring, [20,21] and treatment, or on-demand release of drugs, reactive species, and bactericidal agents [23][24][25][26][27][28] They can serve as miniaturized surgery to repair damaged cells and their scaled-down size allow working operation in remotes areas without losing their physicochemical characteristics and functionalities.…”