Micro combustion and power generation systems have increasingly been investigated as potential alternatives to electrochemical energy storage thanks to hydrocarbon fuel’s high energy density, but electrical componentry for pumping significantly limits the overall system efficiency. These components must be eliminated to allow for widespread adoption of micro combustion and power generation systems, and so the development of an alternative pumping technique is required. By taking advantage of the thermal transpiration phenomenon, small-scale pumping can be obtained in the presence of a temperature gradient. Initial work has been done to investigate the efficacy of this system, but a major issue has arisen due to the lack of low-cost thermal transpiration membranes with desirable pore characteristics. Research has revealed that vessel hyphae present in the roots of mushrooms (mycelium) form a network which could meet the requirements of an effective thermal transpiration membrane. Proper growing conditions could also allow for an application specific mycelium structure providing a highly effective and low-cost thermal transpiration membrane for micro combustion systems.

Increased concerns over climate change, limited fossil fuel resources, emissions, and poor air quality has created a greater need for sustainable energy systems. The need for increased sustainable energy systems has created largely two cooperative movements: 1) technologies that are considered renewable or more environmentally friendly and 2) higher efficiency. The automotive industry has long been a target for increasing efficiency and decreasing environmentally harmful emissions. The combustion of hydrocarbon fuels results in harmful and reactive incomplete combustion byproducts. Fully electric and hybrid powertrains are increasing in commonality but have not yet fully penetrated the market. Many automobile manufacturers are still producing vehicles which rely solely on the internal combustion engine and hydrocarbon-based fuels. Currently, manufacturers utilize a combination of three-way catalytic converters and nitrogen oxide traps to rid the exhaust flow of harmful combustion emissions. Catalytic converters use expensive precious platinum group metals (PGM) to simultaneously react unwanted hydrocarbon, carbon monoxide, and nitrogen oxides into less harmful, complete products of combustion, such as nitrogen, carbon dioxide, and water vapor. However, the performance of these devices is highly dependent upon the equivalence ratio of the exhaust. Three-way catalysts require that the exhaust remain at stoichiometric conditions for optimal performance. Prolonged fuel lean engine operation renders the PGM catalyst incapable of reacting nitrogen oxide emissions. Nitrogen oxide, and more specifically nitric oxide (NO), emissions are of significant concern, as such emissions directly contribute to increased smog, acid rain, climate change, and respiratory inflammation within the population. Lean nitrogen oxide traps (LNTs) are incorporated into the exhaust system to temporarily capture excess nitrogen oxide emissions. However, the zeolite-based materials used in LNTs have a finite limit on nitrogen oxide storage capacity. Once nitrogen oxide capacity is reached, the engine must enter a fuel rich combustion condition or additional reactants must be injected directly into the exhaust system to regenerate the LNT’s function. Therefore, current exhaust treatment measures introduce significant complexity into the exhaust system and significant constraints on engine operation. As such, this work investigates the potential for new exhaust treatment materials, capable of maintaining performance across all conditions. Specifically, this work investigates the NO reduction potential of a multilayered ceramic electrochemical catalytic membrane. Prior work has demonstrated that the natural electric potential oscillation, which develops across such a membrane, significantly reduces NO emissions. The ceramic membrane, consisting of two dissimilar metal electrodes, sandwiching a dielectric layer, is able to achieve an NO reduction in excess of 2X that of a traditional PGM three-way catalytic converter [1]. Here, the possibility for externally inducing a low magnitude (< 500 mVpp), high frequency (> 1kHz) electric potential oscillation across the reacting membrane and increasing the conversion of NO into diatomic nitrogen and oxygen is investigated. Electric potential oscillation at the surface generates an altered electrochemical reaction pathway. During the breakdown of NO, N2O is recorded as an intermediate species without the introduction of NH3. This result diverges from traditional theory, which predicts the formation of NO2. This work further explores the relation between externally applied electric potential oscillation, N2O formation, and reduction of NO.

With the depletion of fossil fuel resources, as well as increasing global temperatures, the interest in sustainable energy is on the rise. Currently, cars are a significant source of harmful emissions due to the use of internal combustion engines. Incomplete combustion byproducts are extremely harmful to the environment and the population, with links to acid rain, smog, and respiratory issues. While green energy solutions, such as electric vehicles, are being developed, the treatment of exhaust can also be an effective way to reduce the release of emissions into the atmosphere. It has been shown that a solid oxide fuel cell (SOFC) is able to break down emissions, even exceeding the capability of typical exhaust treatment methods. An investigation into the usage of an SOFC as an exhaust treatment material has found that the amplification of a signal generated across the cell has an even greater effect on emission reduction. Here, the addition of cesium lead bromide (CsPbBr3) nanocrystals to the fuel cell is being investigated. The SOFC is tested as an exhaust treatment solution and as a power generation device in comparison to a typical SOFC without added CsPbBr3 nanocrystals. CsPbBr3 is a perovskite semiconductor, so it is expected to have an effect on the reactivity of the fuel cell. Investigating the effects of adding nanocrystals into a SOFC will lead to advancements in exhaust treatment systems as well as power generation systems. The work here will show a direct relationship between the quantity of nanocrystals contained in the SOFC to the emission reduction and power generation abilities of the SOFC.