Sustainable Plasma-Catalytic Nitrogen Fixation with Pyramid Shaped μ-Electrode DBD and Titanium Dioxide

This research explores the potential of electric field enforcement in dielectric barrier discharge using specially designed pyramid-shaped mu-electrodes for a plasma-assisted nitrogen fixation process. The obtained results are compared under varying conditions, including the presence and absence of titanium dioxide ( TiO2 ${TiO_2 }$ ), different oxygen concentrations in the nitrogen-feeding gas, and residence time. The results demonstrate that the mu-electrodes lead to an enhancement of nitrogen oxidation, which is further intensified by TiO2 ${TiO_2 }$ . The introduction of 60-70 % oxygen with nitrogen achieves the highest level of NOX ${NO_X }$ production. The synergistic effect of plasma and the catalytic effect of TiO2 ${TiO_2 }$ increase the rate of NOX ${NO_X }$ production by 20 %, resulting in a 23 % increase in energy yield. The introduction of TiO2 ${TiO_2 }$ leads to a sharp increase in NOX ${NO_X }$ production even at lower oxygen concentrations. The crucial role played by ultraviolet light-induced electron-hole pairs in TiO2 ${TiO_2 }$ is highlighted to promote nitrogen oxidation. Nevertheless, it is crucial to emphasize that prolonged residence times may cause the photocatalytic effect to generate alternative byproducts rather than NOX ${NO_X }$ , consequence of excessive oxidation that could prove counterproductive. These findings emphasize the potential of plasma-assisted nitrogen fixation technology in reducing energy costs and meeting the growing demand for sustainable nitrogen-based fertilizers. Pyramid mu-electrodes in plasma enhance nitrogen fixation because such electrodes are suitable for vibrational excitation of nitrogen molecules. Similarly, optimal nitrogen fixation was found with 60-70 % oxygen in the nitrogen feeding gas. Adding titanium dioxide cuts energy costs by 23 % and boosts nitrogen fixation by 20 %. image