Electrodes in environmental systems may provide either a sink or a source for electrons that may be utilized for a variety of catalysis important to the energy-water nexus, water treatment, and environmental restoration. Research in our lab has focused on 1) the interaction between electrodes and biological cells for energy generation and bioremediation.
Reactive Sediment Capping
We are developing environmental remediation strategies for sediment caps based on electrode technology. Our work has revealed that electrodes may be emplaced in a sediment cap to engineer the redox gradient and supply electron donor and acceptor to bacterial communities in the vicinity of the cathode and anode.
Microfluidic Fuel Cells & Biosensors
When supplied with electron donor, pure and mixed cultures of bacteria are capable of producing electricity by respiring the anode in a fuel cells. We have taken advantage of this phenomenon to develop one of the world’s smallest fuel cells (0.3 mL total volume) and simultaneously, a self-powered biosensor.
Capacitive Deionization for Desalination
Capacitive deionization (CDI) is a technology to deionize water by applying an electrical potential difference over two porous carbon electrodes. Anions, ions with a negative charge, are removed from the water and are stored in the positively polarized electrode. Likewise, cations (positive charge) are stored in the cathode, which is the negatively polarized electrode. We have been examining fundamental questions about the role of pore-size on the removal of ions from solutions for desalination using CDI and nanoporous carbonaceous materials and nanoparticle-modified carbon electrodes.