Layer-by-layer self-assembly of nano- And micro-particles as a catalyst integration method for microreactor applications

Hongwei Qiu, Woo Lee

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

Abstract

Commercially available silica spheres in the size range of about 20 nm to 2 µm were initially used as our model catalyst particles for exploring electrostatic layer-by-layer self-assembly, as a novel method of incorporating commercial catalyst powder into a thin-film catalyst structure as an integral part of microreactor fabrication. For the negatively charged SiO2 surface, this method basically consisted of depositing polyelectrolyte multilayers by alternately dipping the substrate into a polycation solution and a polyanion solution. The final polymer surface was made to be positively charged since the silica particles are negatively charged. Substrates that were coated with the polymer film was dipped into silica colloidal suspension and then rinsed in a cleaning solution to electrostatically attach only one layer of the silica particles. The silica particles were immobilized by applying a 1 µm thick sol-gel alumina layer that contained pores with the size of about 3 nm. The overall procedure was refined by systematically studying the effects of pH, ionic strength, and salt and/or buffer concentrations of the polyelectrolyte solutions, the silica colloidal suspension, and the rinsing solutions. The effects of silica particle size on surface coverage and uniformity were assessed. Also, the self-assembly behavior of the model spheres was compared to that observed for ball-milled commercial catalyst powder to assess the practicality of this self-assembly concept.

Original languageEnglish
Title of host publication2005 AIChE Spring National Meeting, Conference Proceedings
Pages2853
Number of pages1
StatePublished - 2005
Event2005 AIChE Spring National Meeting - Atlanta, GA, United States
Duration: 10 Apr 200514 Apr 2005

Publication series

Name2005 AIChE Spring National Meeting, Conference Proceedings

Conference

Conference2005 AIChE Spring National Meeting
Country/TerritoryUnited States
CityAtlanta, GA
Period10/04/0514/04/05

Fingerprint

Dive into the research topics of 'Layer-by-layer self-assembly of nano- And micro-particles as a catalyst integration method for microreactor applications'. Together they form a unique fingerprint.

Cite this