Kinetics and thermodynamics of point defects in non-stoichiometric metal oxides and sulphides

Kinetic methods for studying the transport properties of non-stoichiometric transition metal oxides and sulphides have been described. It has been shown that modern microthermogravimetric techniques enable, in rather simple way, the determination of the concentration and the mobility of point defects in these materials as a function of temperature and oxidant activity, with an accuracy difficult to attain with other, much more complicated and time consuming methods. The advantages of the kinetic methods described in this paper have been illustrated by the results obtained on Mn-MnS-S₂ system which has been extensively studied in detail by different authors using various conventional techniques.