title: Templating CdSe tetrapods at the air/water interface with POPC lipids.
abstract: Surfactants have been widely used as templating agents to pattern the orientation of nanoparticles of various conformations. Here we report the use of a lipid, 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), as a template to order CdSe tetrapods (TPs) at the air/water interface using a Langmuir-Blodgett trough. The surface pressure versus area isotherms for CdSe TPs and CdSe TPs/POPC are examined and monitored by Brewster angle microscopy (BAM). The transferred thin films are further characterized by transmission electron microscopy (TEM) and atomic force microscopy (AFM). Initially disc-like structures containing randomly oriented TPs form during solvent evaporation. Upon decreasing surface area, these discs merge into larger continental structures. In a mixed CdSe TPs/POPC system, these discs organize into wire-like networks upon compression. We detail how lipid molecules can be used to direct the two-dimensional assembly of TPs.
authors.affiliation: Department of Chemical and Biomolecular Engineering, Rice University, Houston, TX 77005, USA.
authors.forename: Kung-Po
authors.initials: KP
authors.lastname: Chao
authors.forename: Hitesh
authors.initials: H
authors.lastname: Bagaria
authors.forename: Michael S
authors.initials: MS
authors.lastname: Wong
authors.forename: Sibani L
authors.initials: SL
authors.lastname: Biswal
mesh_terms: D019187:Cadmium Compounds / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D044367:Phase Transition; D010713:Phosphatidylcholines / Q000737:chemistry*; D011312:Pressure; D018036:Selenium Compounds / Q000737:chemistry*
chemical_list: D019187:Cadmium Compounds; D010713:Phosphatidylcholines; D018036:Selenium Compounds; C058667:cadmium selenide; C028694:1-palmitoyl-2-oleoylphosphatidylcholine