Highly-Ordered Selective Self-Assembly of a Trimeric Cationic Surfactant on a Mica Surface

Original entry: William Bonificio, AP 225, Fall 2009

Information

Highly-Ordered Selective Self-Assembly of a Trimeric Cationic Surfactant on a Mica Surface Yanbo Hou, Meiwen Cao, Manli Deng, Yilin Wang Langmuir 2008 24 (19), 10572-10574

Soft matter keywords

micelle, surfactant, DTAD, bilayer, hydrophobic, hydrophilic

Summary

The purpose of this study was to investigate a novel self assembly on a mica surface. When the researchers allowed (dodecyldimethylammonioacetoxy)diethyltriamine trichloride (DTAD) to assemble on a mica surface nanoscaled parallel stripes formed. This interesting formation is quite unique compared to islands that form on normal surfaces. A suggested mechanism for this ordering was also proposed that draws on many different forces including hydrophbicity and lattice matching.

Soft matter discussion

Chemical structure of DTAD. Notice its trimeric cation structure.

The top two photos show the silicon template used to create the PUA nanofibrils. Below that is finished PUA nanofibrils. Below that show the two shape tuned nanofibrils, the left is the stooped fibril structure, while the right is the crispated fibril structure.

Future devices may have a need for nanoscale structures, so research in this area is booming even without direct applications in mind. To create these structures, many scientists have already noticed that surfactant molecules can self assemble in unique ways; much research has been done on single tailed, or two tailed surfactants. The people in this study however, have used a trimeric structure, DTAD, pictured left.