NanoBio Interfaces

Group Leader: Tijana Rajh

The NanoBio Interfaces Group seeks to understand how deliberate tailoring of multiphase materials at the nanoscale can lead to enhanced functionalities for energy and information transduction. We investigate fundamental parameters that govern energy conversion in functionally integrated multicomponent nanoparticle hybrid systems, capable of energy storage in the form of separated charges. The design of these novel hybrid systems for energy conversion uses nanoparticles for initial light-induced charge separation while biomolecules or inorganic matrixes are utilized for subsequent chemical/electrical conversion. We investigate the role of size, shape, and composition of nanoparticles in physical and chemical properties as well as their reactivity.

Within this program, we develop hybrid nanoparticle structures that combine the properties of different components on the nanoscale leading to new collective properties that arise from the interactions between the individual constituents. For example, we are developing quantum-dot (QD) based solid-state inorganic solutions capable of ionic conductivity, tailored for a new type of photovoltaic cells. The ionic conductive solid matrix with variable redox properties will provide high stability by efficient removal and conducting of photogenerated holes.

Facilities include organic laboratories and clean rooms designed to carry out temperature-controlled, air-free synthesis, enabling these cornerstone capabilities of the group:

• Specialized synthesis of QDs and their assemblies
• Probing the interface of QDs with biomolecules and solid-state matrixes
• Incorporation of these hybrids into devices

Recent highlights include:

• Study of photogenerated charge separation on nano-TiO2-based complex mediated by ene-diol surface ligands EPR and confocal Raman spectroscopy
• Nanobio conjugates for mapping of ligand-receptor interactions through a single cell by the X-ray fluorescence microprobe technique
• Study of plasmon and exciton coupling in metal-semiconductor binary core-shell nanoparticles and doping of semiconductor constituents by intraparticle charge transfer complexes
• Manipulation of interparticle spacing in self-assembled highly periodic single-component structures
• Hybrid composites - bioconjugation of functionalized nanoparticles
• Response of hybrid molecular materials to external stimuli on multiple time and length scales
• Manipulation of biomolecules using nanoparticles
• Nanocatalysis and photocatalysis
• Nanomaterials for energy
• Cellular labeling as well as manipulation of cellular metabolism