Improvement of Oxidation Resistance of Graphite Powder Treated with Phosphate
Graphite powder was treated with lanthanum, aluminum and magnesium phosphate solution, and oxidation resistance of the obtained graphite powder was evaluated. Oxidation starting temperature and oxidation completion temperature of graphite powder treated with various phosphates were 50-100oC higher than those of as-received graphite powder. Graphite powder treated with small amount of lanthanum phosphate exhibited the higher oxidation starting temperature than graphite powder treated with aluminum and magnesium phosphates. LaP5O14 would partially exited on graphite powder, and protect the edge carbon atoms of graphite and reduce the reactivity of carbon atoms toward oxygen, resulting in improving the oxidation resistance.
Katsutoshi Komeya, Yohtaro Matsuo and Takashi Goto
K. Yoshida et al., "Improvement of Oxidation Resistance of Graphite Powder Treated with Phosphate", Key Engineering Materials, Vol. 352, pp. 133-136, 2007