Subcritical and supercritical water: a universal medium for chemical reactions

The results of studies on the properties of subcritical and supercritical water are generalised. The possibility of using such water as a solvent, a reagent or a catalyst in chemical reactions is considered. Primary attention is paid to specific features of experimental research under hydrothermal conditions. Prospects for use of subcritical and supercritical water in heterogeneous catalysis for the preparation of nanocrystalline materials with predictable properties and for solving environmental problems are discussed.