Synthesis of Janus Nanoparticles as Colloidal AmphiphilesJeffrey Pyun, University of Arizona, DMR 1307192

We have demonstrated the ability to make novel Janus nanoparticles composed of a single ferromagnetic dipolar cobalt nanoparticle (CoNP) bound to a single semiconductor CdSe@CdS nanorods. Dipolar assembly of these Janus nanoparticles enable formation of “colloidal polymers” of dipolar CoNPs with nanorod side chains. Surprising these nanorod side chains spread onto supporting substrates when solution cast forming “colloidal bottlebrushes” akin to known molecular bottlebrush macromolecules. (Pyun et al,. ACS Nano 2013 submitted)

Synthesis of Janus Nanoparticles

CdSe@CdS Nanorod Side Chains

Cobalt Nanoparticle Main Chain

Molecular Bottlebrush

Polymers

Matyjaszewski et al. Prog. Polym. Sci.

2008, 33, 759 - 785

Colloidal Bottlebrushes

CdSe@CdS Nanorod Side Chains

Cobalt Nanoparticle Main Chain

Education:Funding from this DMR-POLYMERS award has enabled supported one graduate students, Philip Dirlam (2nd yr graduate student) and three undergraduate researchers, Tristan Klein (from CalPOLY), Kyle Arrington (UA ‘13, now at Virginia Tech-Chemistry) and Jessica Gardin (Northern Arizona University-REU from NSF-STC).

In Fall 2012 and Summer 2013, Phil contributed to the optimized synthesis of dipolar Janus nanoparticles as previouly described and developed synthesis of new polar PEG ligands to prepare amphiphilic colloidal materials. Tristan and Kyle have been focused on new synthetic methods to prepare polymeric nanocomposite materials with enhanced magnetic and electroactive properties. A new collective effort in the Pyun has been centered on Jessica’s research on the use of CdS and CdSe semiconductor nanoparticles and nanorods as photocatalysts for free radical polymerizations. As a key educational effort for these studies has focused on both technical writing and communication. exercised and the Pyun group at UA, Pyun has developed series of summer workshops on professional development skills in technical writing and communication.

Outreach:Continued outreach efforts with Tucson High School in Tucson, has focused on a joint research class (senior, Tucson HS) and work with Ms Jennifer Miller at the Thornydale Elementary School. New efforts at both institutions are being formulated in collaboration with teachers to developed new module on battery science and testing.

A focused research project in collaboration with Rebecca Mulligan (senior) and Ms Margaret Wilch from Tucson High Magnet School was conducted on the fabrication and testing of new Li-batteries. Rebecca received six awards in 2013 for presenting this research, notably 1st prize at the Southern Arizona Regional Science & Engineering Fair, Stockholm Junior Water Prize, The Catalina Rotary Club's Service to Humanity Award, The 2013 Regional Ricoh Sustainable Development Award, The Second Place High School Engineering Award from Texas Instruments

R-MulliganT-KleinP-Dirlam

Synthesis of Janus Nanoparticles as Colloidal AmphiphilesJeffrey Pyun, University of Arizona, DMR 1307192