Effect of temperature and humidity on coarsening behavior of Au nanoparticles embedded in liquid crystalline lipid membrane.
Coarsening behavior of the Au nanoparticles produced by thermal evaporation of Au onto a liquid crystalline lipid (1,2-dioleoyl-3-trimethylammonium-propane, DOTAP) membrane was investigated by subjecting the nanoparticle-embedded DOTAP membrane to two different annealing conditions (at 100 °C under no humidity and at 20 °C and 80% relative humidity). Although the coarsening rate was relatively slow because of the low temperature (from 5.6 nm in the as-deposited state to ~7 nm after 30 h), it was identified that at 100 °C without humidity the Au nanoparticles resulted in shape refinement whereas the high humidity at 20 °C induced self-organization of the nanoparticles into a monolayer. It was also found that annealing in both cases tended to segregate the lipid molecules from the nanoparticle array and forced the nanoparticles into a tighter area. In the case of the high-humidity sample, the lipid segregation eventually led to extensive coalescence of the Au nanoparticles.
Division of Materials Science and Engineering, Hanyang University, Seoul, Korea.
Seung Jae
SJ
Lee
Hyeun Hwan
HH
An
Won Bae
WB
Han
Hee-Soo
HS
Kim
Chong S
CS
Yoon
D006046:Gold / Q000737:chemistry*; D006813:Humidity; D050866:Liquid Crystals / Q000737:chemistry*; D008563:Membrane Lipids / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D013696:Temperature
D008563:Membrane Lipids; D006046:Gold