Duan Research Group

Hetero-integrated Nanostructures and Nanodevices


Colloidal Nanocrystal Synthesis

At the foundation of nanoscience is the formation of nanostructures (particles, wires, sheets, and etc.) that open new possibilities in science and engineering technologies. The ability to tailor the composition, shape, and material properties of these nanostructures is imperative towards practical applications with improving performance. To this end, we utilize biomimetic and chemical approaches towards controlling nanoparticle facets and the way they grow into complex shapes, as well as combining different structures into more advanced heterostructures.

These demonstrations that one can indeed understand and hence manipulate organic-inorganic interfacial interactions, which is of paramount importance especially at the nanoscale where surface to volume ratio is large, through rational molecular design, open up vast opportunities for a wide range of applications from syntheses, catalysis, sensing to energy devices. Our group will continue our efforts in directions of achieving highly functional material structures through rational biomimetic and chemical design. 

With mechanistic studies on the molecular origin of recognition property of the facet-specific peptide (S7) towards platinum {111} facets, we have showed that different binding configurations of phenylalanine create a binding contrast between {111} and {100} surfaces. Understanding this mechanism is essential for the observed facet recognition, and further enables the rational design of small organic molecules that demonstrate preferential adsorptions to {111} facets. Further studies on interfacial interactions between aromatic molecules and noble metal surfaces have demonstrated the electrostatic potential within the conjugated ring system as well as the epitaxial matching between molecules and facets determines the specificity of the adsorption 

The most exciting example of our recent research is the seamless translation of biomolecular recognition properties into small organic molecular designs that can be manipulated to create preferential molecular-inorganic interactions to create nanostructures with predictable morphologies and hence functions. We have designed and demonstrated the identification and implementation of crystal facet-specific peptides to achieve various morphologies of platinum nanocrystals with exquisite controls over both nucleation and growth, achieving outstanding biomimetic control over inorganic materials

UCLA, Department of Chemistry and Biochemistry
607 Charles E. Young Drive East, Box 951569
Los Angeles, CA 90095-1569
E-mail: xduan@chem.ucla.edu