Transition Metal–MoS₂ Reactions: Review and Thermodynamic Predictions

Molybdenum disulfide is a layered transition-metal dichalcogenide semiconductor that is attracting renewed attention for its potential use in future nanoscale electronics, optoelectronics, catalysis, tribology, and other fields. In all of these cases, the interaction between MoS₂ and various transition metals is very important. In this work we survey the thermodynamics of the metal–Mo–S systems and the anticipated reaction products from transition metals and MoS₂. We examined over 200 references on the reactions between transitions metals (M) and MoS₂, compiled thermodynamic data, and used the thermodynamic data to predict M–Mo–S ternary phase diagrams for systems without experimentally determined diagrams. Where possible, experimental literature on the interactions between metals and MoS₂ was used to corroborate our predicted diagrams and stable reaction products. Both the previously reported and newly predicted M–Mo–S phase diagrams fall into three categories. In the first category, the metal is in thermodynamic equilibrium with MoS₂. In another, there is a driving force for the metal to reduce MoS₂, with tie lines to sulfides of the contact metal dominating the phase diagram. In a final category, there is a very stable solid solution or ternary phase that dominates the phase diagram. Better understanding of the phase equilibria in the M–Mo–S systems will aid research on the use of MoS₂ in a variety of fields.