The University of Georgia Riverbend South Building

220 Riverbend Road
Athens, GA 30602.
Off: 706-542-4101
Lab: 706-542-9413

 





ONGOING RESEARCH ACTIVITIES:

Research at NEL is highly interdisciplinary and overlaps with material science, biochemistry, microbiology, biotechnology and analytical chemistry. The end applications that we concentrate most are the following:

  • Enzymatic Fuel Cells
  • Microbial Fuel Cells
  • Electrochemical Biosensors
  • Photosynthetic Energy Harvesting
  • Lithium ion Batteries

Bionanocomposite Materials

 

We are interested in the synthesis, characterization and application of biomaterials that carry electrochemical significance. Our current focus is on enzyme based composite biomaterials that serve as electro catalysts in biological fuel cells and electrochemical biosensors. The primary challenge in these systems is the establishment of effective electrical communication between enzyme redox centers and electrode surface. Our approach toward this problem uses the unique properties of nanostructured materials for establishing direct electron transfer between the electrode and enzyme redox center. In a representative work we used multi-walled carbon nanotubes as conductive supports to immobilize enzymes through a non-covalent surface modification of the carbon nanotubes. We are currently exploring the chemical modification of gold and platinum nanoparticles for bio-electrochemical applications including biosensors, bio fuel cells and bio electronic chips.

Small Scale Electrochemistry

 

We use scanning electrochemical microscopy (SECM), atomic force microscopy (AFM) and other scanning probe microscopy (SPM) techniques to image, interact, probe and characterize the electro-active species on biological surfaces at microscopic scales. Of particular interest in the probing of microbial biofilms to study the fundamental relationships between microbiological and electrochemical properties over a microscopic domain of the biofilm, without the interference from bulk mass transfer effects. The interactive response of the biofilm is compared to the microbial fuel cell performance at different external conditions to understand the true impact of the external effects on the bio-electrochemical properties of the microbes.  An extension of similar approach is applicable to study the bio-electrochemical interfaces of enzymatic electrode systems in biosensors and enzymatic fuel cells.

Electro-active Microbial Biofilms

 

The unused free energy in microbial metabolism is partially recovered as electricity in microbial fuel cells. The ‘work horse’ of a microbial fuel cell is the anode biofilm, which is synonymous to the catalyst layer of a fuel cell. Microbes use soluble mediators, outer membranes cytochromes and/no pili nanowires to deliver electrons (electricity) to the electrode. This is a highly complex bio-electrochemical process that is very difficult to understand using simple characterization techniques. We combine the optical microscopy tools with online, in-situ electrochemical characterization techniques to understand the fundamental of bio-electrochemical processes occurring in biofilms. We extract specific parameters to help us engineering/architect better biofilms for high power output in microbial fuel cells.

Biosensors for Early Disease Detection in Produce

 

 

Electrochemical biosensors have applications in multiple fields including medicine, environment, military reconnaissance and agriculture. Our current focus is on the development of biosensors often dubbed as ‘electronic nose’ for early detection of pathogenic diseases in agricultural produce. We also collaborate with Dr. Glen Rains to explore the possibility of early detection of parasite infestations in agricultural crops using biomimetic electrochemical sensors based on the olfactory receptors of parasitoid insects.

Electrochemical Power from Photosynthesis

 

 

We are currently developing bio-electrodes based on immobilized plant pigments to harvest light energy. These electrodes will be used in photosynthetic electrochemical cells that convert direct into eelctricity with no external fuel.

Structured Nanocomposites for Li-Ion Batteries

 

 

Silicon based anode materials gained a lot of attention in the recent years due to their high specific capacity. But the stress-induced capacity loss during cycling is a major disadvantage with silicon-based materials. We are currently working on Cu, Mg and Mn based silicon composite materials to be used as anode in lithium ion batteries.