1999 年 67 巻 2 号 p. 155-159
In order to improve the durability of phosphoric acid fuel cells (PAFC), it is essential to suppress the corrosion rate of carbon, which is one of the important components. In this study, we examined the influence of the degree of graphitization of carbon materials on their corrosion rate in hot phosphoric acid. We found the higher the level of graphitized carbon the lesser corrosion rate. In the case of using a pitch as a precursor, a graphitization temperature of at least 2000℃ was needed to suppress the corrosion rate. Treatment at higher temperatures did not affect corrosion suppression. Alternatively, a layer dimension parameter-Lc or La-of over 200 or 300 was needed.