Metal‐Carbon Composite Materials from Fiber Precursors: I . Preparation of Stainless Steel—Carbon Composite Electrodes

Abstract

A novel approach to fabrication of composite metal‐carbon electrodes has been developed. Stainless steel fibers (2 μm diam) and carbon fiber bundles (20 μm diam) were combined with cellulose (as the binding agent) into an interwoven paper preform. The composite paper preform was then sintered to a stainless foil substrate to form the electrode structure. “Optimal sintering,” experimentally determined by the percentage of initial carbon remaining in the sintered electrode, was achieved at 1423 K in H2 for 2.5 min. Gas flow of H2 was maintained at 10 cm3/min (STP) or a linear velocity of 2.6 cm/min with a total pressure of 101 kPa. These conditions were consistent with the thermodynamics and kinetics of sintering and catalyzed carbon gasification. The composite electrode structure was shown to possess the high surface area characteristic of carbon black and the structural integrity of sintered metals. The degree of intermixing of fibers in the composite paper preforms and in the sintered electrodes was clearly shown by scanning electron microscopy (SEM). Volumetric BET measurements showed a surface area of ca. 760 m2/g of carbon for the sintered composite electrode structure compared to ca. 790 m2/g for the precursor carbon fiber. It is believed these preparation techniques offer flexibility in the properties of the composite electrode (i.e., specific surface area, void volume, thermal and electrical conductivity, etc.).

Characterization of Dirt Holding Capacity of Microfiber-Based Filter Media Using Thermal Impedance Spectroscopy

“…The VGCFs were consequently chosen as the applicable nanofibers for this novel filter media fabrication in our laboratories. , The large van der Waals force and high surface energy between VGCFs cause bundling of the VGCFs with bundles ranging in diameter from a few hundred microns to a few millimeters. Based on the method developed by the Auburn CM3 group, − the VGCFs have been successfully separated, flocked, and dispersed into the wet-laid nonwoven filtration media with polymers and activated carbon fibers. The nonwoven nanofloc filter media has been successfully developed by embedding nanoflocs into microfiber support structures via a wet-lay process.…”

A novel nano-nonwoven fabric with three-dimensionally dispersed nanofibers: entrapment of carbon nanofibers within nonwovens using the wet-lay process

“…) shows the SEM image of as-received VGCF clumps that were dispersed and then flocked. The SEM images of the final sintered nickel nonwovens with varying quantities of VGCF are shown in figures 5(b)-(e).One concern during metal nonwoven sintering was the catalytic gasification of entrapped carbon[23][24][25]. The sintering conditions were simulated in a thermal gravimetric analyzer (TGA) to check for the loss of VGCF due to catalytic gasification.…”

Electrochemical Reduction of Oxygen at “Electrocoated” Nafion‐Modified Metal‐Carbon Composite and Platinum Electrodes

“…Tatarchuk et al 13,14 recently have reported the development and preliminary characterization of a stainless steelcarbon composite electrode which combines the high surface area of activated carbon fibers with the high conductivity of stainless steel fibers into a self-supporting sintered network. The electrodes are highly permeable to liquids and gases and have excellent electrical conductivity.…”