Nanoscience at UMCP

1. Nanoscience at UMCP

2. Department of Chemistry and Biochemistry Faculty: Jeff Davis, Bryan Eichhorn, Doug English, Lyle Isaacs, Jason Kahn, Janice Reutt-Robey, Larry Sita, and Rob Walker Research Expertise: • Molecular Synthesis and Self-Assembly • Mesoscale Self-Assembly in Aqueous Environment • Controlled Biomimetic Hierachical Organization • Smart Materials and Sensors • Self-Replicating Systems • Supramolecular Organization of Block Copolymers • Magnetic Nanostructures • ‘Soft’ Materials Synthesis • Chemical Derivatization of Surfaces and Interfaces • Nanotubes • Molecular Electronics • Single Molecule Spectroscopy Characterization : NMR, AFM, STM, XPS, Single Crystal and X-ray Diffraction, MFM, SEM, TEM, SQUID, Electrospray Mass Spectroscopy, Single Molecule and Surface Optical Spectroscopies

3. Nanostructured and Bio-inspired Materials Mission: The controlled assembly of ‘soft’ functional nanostructures via the manipulation of ‘weak’ forces, including: • hydrogen-bonding • electrostatics • hydrophobic effects / solvation • microphase separation • metal coordination • supramolecular assembly Definition: The term ‘soft’ defines: • environment (e.g. aqueous or interfaces) • nature of subunit interactions (i.e. noncovalent, thus, both • thermodynamic and kinetic assemblies possible) • conditions for synthesis (e.g. low temperature production • of ‘hard’ nanostructures) Range: ‘soft’ nanostructures encompass the pure chemical to the pure biological

4. Target Systems • ‘Bionics’ • Self-replicating • Self-repairing • Nano muscles and nanomechanical devices • Nano pores and channels • Vesicles and capsules • Motors and Actuators • Frameworks and Armature • Micron-scale assembles from nanoscale constructs (2) ‘Soft’ Assembly of ‘Hard’ Nanostructures • Low temperature and shape-selective routes to dots, • nanotubes, whiskers and asymmetric shapes of • carbon, semiconductors, and metal • Templated assembly of 2- and 3-D arrays of hard • nanostructures for device fabrication • Metastable structures

5. Target Systems (3) Surfaces and Interfaces: • Control of electron transport • Control of solute / surface interactions • Nanoporous membranes • Nanolithography • Electrochemical and Optical sensors • Platforms for hierarchal organization of biostructures • and cells.

6. Artificial Ion Channels via Self-Assembly Davis Group Hydrogen-Bonded G Quartet Crystal Structure of a Filled K+ Ion Channel Oxygen-Rich Pore Hydrophobic Exterior Selective K+ Ion Transport Across Bilayer Membrane

7. 5 s 1 pA closed opened Calix Amide pH pulse Triton X-100 NaCl Na2SO4 Artificial Ion Channels via Self-Assembly Davis Group Calixarene tetramide – potential antibiotic Aggregation in the presence of HCl Selective Transport of Cl- Anion Formation of Ion Channels

8. Hydrophobic Self-Assembly in Water Isaacs Group Self-Complementary Facile Amphiphiles Form Dimers in Aqueous Environment Crystal Structure Solution NMR Analytical Ultracentrifugation

9. Triggered Enantiomeric Self-Recognition Isaacs Group

10. Nanostructured Materials via “Soft” Synthesis Eichhorn Group Microscale (cannot easily functionalize) Microscale Metastable Bulk Materials precursors Nanoscale Molecules (no bulk properties) • retain bulk properties • retain molecular (kinetic) control • cation and anion metathesis over short distances • low temperature reactions / functional groups

11. Refractory ZrN layer (-CN) layer m 10 nm ~20 nm metastable hexagonal nanocrystal Nanoscale Synthesis of Functionalized Refractories Eichhorn Group Organic / Inorganic Metastable Materials ZrN(CN)x Electron diffraction of nanocrystal

12. Molecular Electronics Sita Group Concept Demonstration of Two-State System Conduction Physics of Single Molecules Tapping Mode AFM Image

13. Supramolecular Polymer Chemistry Sita Group Architectural Control Metal Nanostructures Au nanocrystals (1 nm dia) Cu nanostructures (20 nm wide)