The nonstoichiometry of the equilibrium phases is an important aspect in the study of equilibrium between transition-metals and their oxides. This paper reports our measurement on the deviation from stoichiometry in oxygen-deficient MoO2-x. A diagram showing real oxygen potential isotherms for non-stoichiometric MoO2 and Mo in equilibrium was given. The correction for the standard free energy of formation of MoO2 has been conducted and the Smiltens' intergration used for the pure metal side has been discussed.

本文使用自行设计的热重装置对MoO2-M0系中间氧化物热力学稳定性及金属-氧化物平衡作TH2O/H2气氛下气态平衡法的研究。在PH2O/PH2从0.123到0.507，温度由625至912℃范围内直接测定了反应1 2MoO2+H2=1 2Mo+H2O（g）的平衡常数。平衡常数Kp与绝对温度T之间的关系可表达为方程：lgKp=1.612-2257.7 T。实验表明，MosO，MoO和Mo2O3等中间氧化物在本研究的温度和氧压范围内不能作为热力学稳定相存在。