HYDROGEN AND OXYGEN EVOLUTION ON GRAPHITE FIBER-EPOXY MATRIX COMPOSITE ELECTRODES.

Article abstract of DOI:10.1016/S0013-4686(98)80004-2

The electrochemical behavior of three graphite fiber-epoxy matrix composite materials containing various fiber orientations and fiber loadings was studied. Cyclic voltammetry was used to detect surface functionalities and to determine the electrochemically active surface areas of each material in 1 N H//2SO//4 and 30 weight percent (w/o) KOH. Hydrogen and oxygen evolution were studied on each electrode in 1 N H//2SO//4 and 30 w/o KOH, respectively. Tafel slopes for the hydrogen evolution reaction on the composite electrodes ranged from 0. 14 to 0. 18 V decade** minus **1 while exchange current densities ranged from 4 to 11 multiplied by 10** minus **7 A cm** minus **2. Tafel slopes for the oxygen evolution reaction on the composite materials were high, ranging from 0. 25 to 0. 28 V decade** minus **1.