Research on the effect of catalyst structure on an air-breathing microfluidic fuel cell with crevice

The microfluidic fuel cell (MFC) takes advantages of small volume, portable structure, sustainable operation, and no pollution, making them provide a promising application prospect in miniaturized electronic devices. However, the poor output power density and low fuel utilization limit their practical applications. To address these issues, a novel design of dual-cell MFC with crevices has been proposed to alleviate the ionic resistance and improve the fuel utilization and output power density. In this paper, the constructed numerical model is validated by comparing with reported experimental data. The MFC with 0.1 mm crevice achieves the maximum power density of 77.2 W m-2 and maximum fuel efficiency of 17.32%, which also can economize cathode catalyst material. The optimal flow velocity of 1 mL min-1 is obtained, which demonstrates the maximum power density of 180.6 W m-2 and maximum current density of 897.4 A m-2. A large fuel concentration is beneficial to improve the MFC power density but is adverse to the fuel efficiency. The research results are helpful to reveal the underlying mechanisms of convection-diffusion-reaction process in MFC, which may provide significant theoretical suggestions for the practical applications.