Our research focuses on nanoparticles science. Three major directions are pursued:
1. Solution processed solar cells with absorber layer made from nanoparticles precursors
Three forms of thin-film solar panels have been developed and commercialized in the last decade by identifying materials that are both efficient absorbers of solar power and cost-effective for manufacturer and consumer; these are: amorphous silicon (a-Si), cadmium telluride (CdTe) and CIGS (copper indium gallium sulfo-selenide). Although they operate effectively in thin-film (1-3 microns), there are both environmental and economic concerns for the cost and sustainability of the materials and processes employed in these approaches.
Our solar research is focused on absorber materials that are both sustainable and amenable to solution processing. The typical solar cell structure pursued in our lab is illustrated in below, where the absorber layer is selected from the group of FeS2 and derivatives.
The materials of interest are generated by a bottom-up approach using nanoparticles precursors to build the absorber layer. The overall fabrication process of our solar cells is in illustrated in the schematic below.
2. Biomedical applications: sensing neuron-astrocytes communcation
Recent research in brain cells intercommunication revealed that astrocytes serve a more complex role than just support for neuronal growth. Astrocytes are organized as networks and communicate with each other, thereby affecting larger neural circuits. They also provide a link between neurons and the vasculature, potentially changing the cerebral microcirculation.
We are developing silica-based sensing nano-materials to interrogate the neuron-astrocyte communication in simulated in-vitro brain environments. The unique aspect of this research is that enables identification of neurotransmitter molecules released in the neuron-neuron-astrocyte tri-synapses with temporal and spatial resolution toward understanding the role of astrocytes in regulating neuronal function.
3. Engineered nanoparticles - toxicity testing
Nanoparticles are becoming ubiquitous additions to everyday products because of the special optical, electrical, structural, or anti-microbial properties that their macro counterparts do not possess. Most nano-scale materials are either metal or metal oxide based (silver, titanium dioxide, cerium oxides, quantum dots) or are carbon based (fullerenes, carbon nanotubes, carbon nanofibers).
Since nanotechnology is progressing at such a fast pace and nanomaterials are being incorporated into new products every day, it is important that we fully understand the implications for their ultimate and unavoidable release into the environment. Recent complaints in regard to consumer products from cosmetic industry such as sunscreens, different skincare formulations etc. containing nanoparticles like titanium dioxide (TiO2), zinc oxide (ZnO) and silver (Ag) among other components, reflect the need for a thorough investigation of these types of engineered nanoparticles in respect to their toxicity. We are fabricating nanoparticles of titanium dioxide (TiO2), zinc oxide (ZnO) and silver (Ag) by chemical and mecano-chemical methods and are investigating their toxicity in different cell.