Principal Investigator Jung-Hoon Chun
Fuel cells are used to convert chemical energy stored in a fuel directly to electrical work without the need for combustion. Direct methanol fuel cells (DMFCs) use methanol, an energy dense liquid, as the fuel in place of the more common hydrogen. The simplicity of liquid fuel storage and the large energy density of methanol make DMFCs a leading candidate to replace lithium-ion batteries as the power source of choice for power-hungry portable electronics of the future. Fuel cell research in the LMP is focused on the design and characterization of novel DMFC electrodes. These electrodes are designed such that they will be highly catalytically active, inexpensive, and durable over the life of the fuel cell.
Despite the appeal of fuel cells as energy conversion devices, there are many obstacles to their commercialization. Primary amongst these obstacles is that the electrochemical reduction of oxygen is an inherently slow reaction, and that the best available catalyst for this reaction is platinum. The result of these two factors is that fuel cells are expensive and have limited power densities. Absent a catalyst superior to platinum, we are left to engineer a fuel cell to maximize platinum surface area and utilization so as to achieve the higher power densities with lower amounts of platinum catalyst. Much of fuel cells research has focued on achieving these ends by engineering electrodes with higher internal surface areas. However, this is often to the detriment of the mass transport or reactants within the electrode. The focus of our research in this area is on the engineering of fuel cells with improved mass transfer as compared with fine pore gas diffusion electrodes. With improved mass transfer it becomes possible to increase the utilization of platinum and therefore generate higher overall reaction rates from a given mass of platinum catalyst, ultimately resulting in a fuel cell with higher power density at a lower cost.