Elimination of water flooding of cathode current collector of micro passive direct methanol fuel cell by superhydrophilic surface treatment

To solve the water flooding problem of micro passive direct methanol fuel cell (DMFC), plasma electrolytic oxidation (PEO) was adopted to prepare a superhydrophilic coating on the surface of an aluminum-based cathode current collector which contacts with air. Results data show that liquid water spreads quickly as a plane on the surface of the porous PEO coating that is composed of Al₂SiO₃ and Al₂O₃. As a result, water droplet can be prevented from accumulating along the air-breathing channels of the PEO-treated cathode current collector, and thus the water flooding problem of the micro passive DMFC is effectively solved. The cell fabricated with the novel cathode structure gives excellent stability.