MS&E Colloquium: Prof. V. Renugopalakrishnan, Northeastern University
Date: January 30, 2009 from 2:00 pm to 3:00 pm EST
Location: Columbia University
Morningside Campus
214 S. W. Mudd Building
Contact: For further information regarding this event, please contact Chad Gurley by sending email to cg2029@columbia.edu .
Info: Click Here to Visit Website.
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Prof. V. Renugopalakrishnan
Northeastern University


Alternate Sources of Green Renewable Energy: An Approach From Nanoscience, Life Sciences & Materials S
cience

 

World energy needs are rapidly escalating and the major source of energy, fossil fuels, are declining at an astounding rate. Among the renewable sources of energy, the sun's energy remains under utilized. Nature has crafted elaborate photosynthetic machinery for harnessing the  sun's energy, which consists of a number of photoactive proteins that synchronize their function to make photosynthesis very efficient. An important achievement in solar cells has been the development of dye sensitized solar cells (DSSC). Bio sensitized solar cells (BSSC) derive their inspiration from the relatively less understood and appreciated phenomenon of photon triggered electron ejection by light activated proteins. DSSC and BSSC differ in the electron donor - ruthenium II complex (Ru) dye in the former and light activated protein in the later. Similar to DSSC, the electron acceptor remains TiO2 and ZnO in various morphologies. Many factors contribute to the very high efficiency of photosynthesis including the role of quantum coherence which preserves electronic coherence in photosynthetic complexes and allow the excitations to move coherently in space promoting highly efficient harvesting of suns. This emerging nascent technology holds promise for the future in providing yet another weapon in the rapidly developing arsenal of technologies to harness solar energy. Coupled with environmentally friendly conducting polymers or even replacing them with wide gap protein-based semiconductors would propel this new technology to the forefront in the near future.

Bio-fuel cells (BFC) are energy-conversion devices based on bio-electrocatalysts available from enzymes or micro-organisms deriving power from biological macromolecules. Such devices could be implanted in a human patient to power microsensors such as monitors for blood pressure, temperature, metabolite concentrations, or glucose sensors for diabetics. Despite their vast potential, there are no BFCs operating on the scale required for several "real world" applications (~1 cm3). A major design goal is therefore to improve BFC efficiency, which presents several technological challenges: (1) increasing the power density, (2) achieving sufficient electron flow between biocatalysts and electrodes, and (3) preserving the structural integrity of biocatalyst-electrode adducts in the BFC. Understanding the determinants that govern the efficiency, stability and kinetics of the bioreactions is an equally important challenge for the commercialization of BFCs.