Colloidal Assembly and Separation under UV‐Induced Convective Flows and on Inclines. Issue 7 (6th April 2021)

• Record Type: Journal Article
• Authors: Kauffman, Joshua E.; Tansi, Benjamin M.; LaSalle, Christopher; Manna, Raj Kumar; Shklyaev, Oleg E.; Balazs, Anna C.; Sen, Ayusman
• Is Part Of: ChemNanoMat. Volume 7:Issue 7(2021)
• Page Start: 805
• Page End: 810
• Publication Date: 2021-04-06
• Subjects: Assembly -- colloids -- convection -- photothermal effect -- plasmonic nanoparticles -- separation; Nanochemistry -- Periodicals; Nanostructured materials -- Periodicals; Nanochemistry; Nanostructured materials; Periodicals; 541.2
• DOI: 10.1002/cnma.202100082
• Languages: English
• ISSNs: 2199-692X

Abstract

Abstract: Achieving directed motility and separation of colloidal particles is a crucial requirement in a range of technological areas. Herein, we describe a system that exploits the photothermal properties of plasmonic nanoparticles for the assembly and separation of larger microparticles. Irradiating an aqueous suspension of gold or silver nanoparticles with UV light generates thermal convection which can be used to move and organize larger particles. Moving the UV light source allows the relocation of the particle cluster. In addition, thermal convection can be used to separate inert particles of different sizes on an inclined plane. Since fluid motion stems from thermal convection, collection and separation can be reversed simply by turning off the UV light enabling a rapid on‐demand response system. Abstract : Illuminating an aqueous solution of plasmonic gold or silver nanoparticles with ultraviolet (UV) light generates convective flows. The flow velocity can be controlled by altering the size of the metal nanoparticles. These convective flows can be harnessed to move, assemble, and separate larger microparticles on an incline. The process can be reversed by turning off the light, enabling a rapid on‐demand response.