Electrical conductivity anomaly in near-stoichiometric plutonium dioxide

• Published in: Journal of nuclear materials Vol. 95; no. 1; pp. 181 - 184
• Main Authors: Naito, Keiji, Tsuji, Toshihide, Ouchi, Kinji, Yahata, Taneaki, Yamashita, Toshiyuki, Tagawa, Hiroaki
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.01.1980
• ISSN: 0022-3115; 1873-4820
• DOI: 10.1016/0022-3115(80)90092-6

The variation of the electrical conductivity with oxygen pressure has been measured for plutonium dioxide at temperatures between 950 and 1100°C and in the oxygen partial pressure range from 2.1 × 10 4 to 10 −11 Pa. Minima in electrical conductivity and corresponding transitions from n- to p-type conduction as function of the oxygen partial pressure were observed. These minima could occur by the presence of some impurities, but the possibility of the existence of hyperstoichiometric PuO 2 also could not be excluded by considering the concentration of the impurities. An intrinsic band-gap energy of 2.5 eV was calculated from the temperature dependence of the minimum electrical conductivity. The slopes of the plot of log o against log PO 2 for the n-type region were − 1 4.99 , − 1 4.72 , − 1 4.77 and − 1 4.81 at 950,1000, 1050 and 1100°C, respectively, which are in good agreement with the values reported previously. The ionized oxygen vacancy model seems to be reasonable in the n-type region.