Fibrous metal-carbon composite structures as gas diffusion electrodes for use in alkaline electrolyte

• Published in: Journal of applied electrochemistry Vol. 27; no. 1; pp. 9 - 17
• Main Authors: AHN, S, TATARCHUK, B. J
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 1997
• Subjects: Chemistry; Electrochemistry; Electrodes: preparations and properties; Exact sciences and technology; General and physical chemistry; Other electrodes; Scanning electron microscopy; Oxygen; Electrode production; Basic solution; Critical parameter; Gas electrode; Experimental study; Composite material; Inorganic compound; Surface structure; Electrodes; Thickness; Chemical reduction; Potassium Hydroxides; Stainless steel; Morphology; Electrochemical reaction; Current density; Carbon fiber
• ISSN: 0021-891X; 1572-8838
• DOI: 10.1023/A:1026454513293

The fabrication of novel fiber composite electrode structures and the performance assessments for oxygen reduction in alkaline electrolyte is reported. An array of 2 mu m diameter activated carbon fibers interlocked within a network of 2 mu m sinter-bonded stainless steel fibers to form the composite structure was used. The resulting electrode structure is stable, highly conductive, and can maintain void fraction > 95%. Electrode physical properties including thickness, macroporosity, and volume and mass fractions of constituent carbon and metal fibers have been controlled, characterized, and related to the electrode polarization in a KOH half cell. Comparison have been made with a commercial Teflon-bonded gas diffusion electrode (GDE). It has been demonstrated that this novel method allows reproducible and low-cost fabrication of GDEs with the optimal balance between macropores for gas access, micropores for liquid access, and conductive paths for electron access.