Block Copolymer Self-Assembly for Precision Nanomaterials

Friday, October 13, 2017


Dr. Morgan Stefik

Department of Chemistry and Biochemistry

University of South Carolina

Hand 1144, 3:30 PMstefik

Abstract. Few aspects are as prevalent and important to energy conversion and storage as the dimension control of porous nanomaterial architectures. The equilibrium self-assembly of block copolymer has historically led to numerous morphologies and nanomaterials, however the constraints of any equilibrating approach impose significant limitations on the extent of control. Broadly, the lack of well-defined nanomaterial series has hampered the study of electrochemical devices. A key challenge is achieving independent control over the pore and wall dimensions to enable ideal studies with well-defined and independent architectural parameters, a feature that is impossible under equilibration. In my talk, I will focus on recent developments with a new nanofabrication tool kit based upon the kinetic control of block copolymer micelles. These micelles are used to template functional nanomaterials for energy applications. Here, the use of kinetic control uniquely enables sample series with constant morphology (isomorphic) to eliminate the performance effects of varying pathway connectivity. The kinetic control of block copolymers is historically difficult to reproduce, a challenge that we have resolved with switchable micelle entrapment to yield reproducible and homogeneous nanomaterial series that follow model predictions. This approach enables seamless access from meso-to-macroporous (10-100 nm) materials with an unprecedented ~2 Å precision of tuning, commensurate with the underlying atomic dimensions. This precision and independent control of feature dimensions also opens new opportunities for self-assembly approaches to broadly enable nano-optimized devices.

 

References

1) Lokupitiya, H. N.; Jones, A.; Reid, B.; Guldin, S.; Stefik M.* Chem. Mater. 2016, 28(6), 1653-1667. 

2) Sarkar, A.; Stefik, M.* J. Mater. Chem. A 2017, 5, 11840-11853.

3) Lokupitiya, H. N.; Stefik, M.* Nanoscale 2017, 9, 1393-1397.

4) Stefik, M.* Chem. Sus. Chem. 20169, 1727-1735. 

5) Lamm, B.; Sarkar, A. Stefik, M.* J. Mater. Chem. A 20175, 6060 – 6069.

6) Peters, K.; Lokupitiya, H. N.; Sarauli, D.; Labs, M.; Pribil, M.; Rathousky, J.; Kuhn, A.; Leister*, D.;
Stefik, M.*; Fattakhova-Rohfling, D.* Adv. Func. Mater. 2016, 26, 6682–6692. 

 

Morgan Stefik obtained a degree in Materials Engineering from Cal Poly SLO in 2005 before completing doctoral studies in Materials Science at Cornell University under Prof. U. Wiesner and Prof. F. J. DiSalvo in 2010. After two years of postdoctoral research at École Polytechnique Fédérale de Lausanne with Prof. M. Grätzel, he joined the University of South Carolina in 2013 as an Assistant Professor in the Department of Chemistry and Biochemistry. He is the founding director of the South Carolina SAXS Collaborative, a NSF supported facility.


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