Nanotechnology and Bio-energy

1. Nanotechnology and Bio-energy By: Miranda Cozza

2. My Article Bio-Batteries and Bio-Fuel Cells: Leveraging on Electronic Charge Transfer Proteins By: A. M. Kannan, V. Renugopalakrishnan, S. Filipek, P. Li, G. F. Audette, and L. Munukutla

3. Nanotechnology • Nanotechnology is a branch of physical • science which deals with the study and analysis of • matter on an atomic or molecular scale to yield new • structures, devices, materials, systems and catalysts • with unique and extraordinary properties. • This technology can provide us quicker, faster and more • reliable methods to optimize the energy generation • from the biological sources. • Products based on nanotechnology that are available today have an extremely diverse background, ranging from industrial measuring and sensing devices, therapeutic • systems and consumer friendly goods such as wrinkles • resistant clothes, tubeless tires and so on.

4. Introduction: Bio-Fuel Cells • Energy- conversion device based on bio-electrocatalysis leveraging on enzymes or microorganisms. • Either through Direct Electron transfer- where electron transfer is directly between enzymes and electrodes • Or Mediated electron transfer- in which electron shuttle mediators shuttle the electron between enzymes and electrodyes • DET is more desirable • We are going to be using miniature cells to derive power from biological macromolecules

5. Bio-fuel Cell Continued and Bio-Battery • Galvani discovered that biological pathways have a bioelectrochemical facet • This is because an electron signal can induce biological reaction; and the same goes in the reverse. • First microbial biofuel demonstrated in 1912 • But first enzyme-based bio-fuel cell only reported in 1964 using glucose oxidase – anodic catalyst and glucose as bio fuel • Bio Battery – generates electricity from carbohydrates by using enzymes as the catalysts • Glucose → Gluconolactone+2H+2e− • O2 +4H+4e− → 2H2O

6. Previous Attempts of Bio-fuel Cells • Several potential applications of BFCs have been reported • However, there are no Bio fuel design templates that allow for the production of a working device with a size on the order of 1 cc • due to the difficulty for enzymes to attain direct electrical contact with the electrodes of the cell and catalyze reactions effectively • Two large obstacles with bio-fuel cell • Increasing power density • And increasing enzyme stability

7. Technical Challenges of Bio-Fuel Cells Nanostructured bioelectrocatalysis. 2. Immobilization of bioelectrocatalysts. 3. Protein denaturation induced by CNT

8. Nanostructured Bioelectrocatalysis • Bio fuel cells need catalyst • Example • virus-based lithium-ion biobatteries. • There is an increasing need for smaller and more flexible Li ion batteries methods to assemble battery materials in various applications. • However, realizing smaller and flexible battery systems need monodisperse, homogeneous nanomaterials and hierarchical organization control.

9. Immobilized Bioelectrocatalyst on CNTs (Carbon Nanotubes) • In order to promote DET of the protein and to improve • the stability, it is necessary that the protein is immobilized in the form of clusters. • Recent study that CEC-Gox did not manifest in activity after 250 days • This is due to the CNTS • Carbon nanotubes have potential to allow new 3-dimensional CNT- Gox anode structures • From the researcher laboratories of this article they found that the CNT – lead to denaturation of proteins

10. Electron Transfer • Most of bio-molecular electronic or protein based devices hinge on ECT (Electron charge transfer) • Protein bearing transition metals such as Cu2+ and Fe 2+ play leading roles in Electron transport • Flavoproteins- used in electron charge transfer • Oxidoreductases- main Glucose Oxidase (GOx)

11. Glucose Oxidase (Gox) • Article focused on Gox as a test case for covalent attachment to substrates • Discovered- covalent attachment of Gox to SWCNT(single – walled carbon nanotubes) enhances the efficient transfer of electrons

12. Conclusion!!! • By engineering a approach that significantly simplifies the process of bio fuel cells; done by • there is no need for thin film depositions or any other surface pretreatment • there is no preference for the semiconductor or metal used • and is easily adaptable to nanostructured surfaces.

13. Critique/ Future work • This article was very interesting but they did not really show what kind of experimentation went on to discover their findings. They just explained more about things that were known or needed a solution too. • The one thing that bothered me is that they talked about how crosslinking with CNTs could cause denaturation, but never explained how or proposed a solution. This could be future work. • At the end it talks about the packaging of bio-fuel cells and how there are many challenges to incorporate nanotechnology into the fuel cell and mass produce it. This could also be future work.

14. References • Kannan, A. M., et al. "Bio-Batteries and Bio-Fuel Cells: Leveraging on Electronic Charge Transfer Proteins." Nanoscience and Nanotechnology (2008): 1-13. Document. • F.Davis and S.P.J.Higson, Biosens. Bioelectron. 22, 1224 (2007) • . M.C.Potter, Proceedings of the Royal Society B, Biological Sciences 84, 260 (1912). • A.T.Yahiro, S.M.Lee, and D.O.Kimble, Bioelectrochemistry: • Enzyme utilizing bio-fuel cell studies, Biochimica et BiophysicaActa (BBA)—Specialized Section on Biophysical Subjects 88, 37 • A.Heller, Phys. Chem. Chem. Phys. 6, 209 (2004) and references therein

15. Questions and Answers!