The gating effect by thousands of bubble-propelled micromotors in macroscale channels. Issue 27 (18th June 2015)

• Record Type: Journal Article
• Authors: Teo, Wei Zhe; Wang, Hong; Pumera, Martin
• Is Part Of: Nanoscale. Volume 7:Issue 27(2015)
• Page Start: 11575
• Page End: 11579
• Publication Date: 2015-06-18
• Subjects: Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/c5nr02562a
• Languages: English
• ISSNs: 2040-3364

Abstract

Abstract : The presence of active bubble-propelled micromotors in large numbers (>10 000) was found to slow down the dissolution and dispersion of chemicals. Abstract : Increasing interest in the utilization of self-propelled micro-/nanomotors for environmental remediation requires the examination of their efficiency at the macroscale level. As such, we investigated the effect of micro-/nanomotors' propulsion and bubbling on the rate of sodium hydroxide dissolution and the subsequent dispersion of OH − ions across more than 30 cm, so as to understand how these factors might affect the dispersion of remediation agents in real systems which might require these agents to travel long distances to reach the pollutants. Experimental results showed that the presence of large numbers of active bubble-propelled tubular bimetallic Cu/Pt micromotors (4.5 × 10 4 ) induced a gating effect on the dissolution and dispersion process, slowing down the change in pH of the solution considerably. The retardation was found to be dependent on the number of active micromotors present in the range of 1.5 × 10 4 to 4.5 × 10 4 micromotors. At lower numbers (0.75 × 10 4 ), however, propelling micromotors did speed up the dissolution and dispersion process. The understanding of the combined effects of large number of micro-/nanomotors' motion and bubbling on its macroscale mixing behavior is of significant importance for future applications of these devices.