Abstract: Described herein are methods, systems, and techniques relating to clathrate hydrate formation processes and, particularly, involving reactive metal nucleation substrates for promoting clathrate hydrate formation. The disclosed methods, systems, and techniques allow for improved nucleation rate and yield of clathrate hydrates. In some cases, the disclosed methods, systems, and techniques can also improve or reduce the amount of time needed for obtaining a given quantity of clathrate hydrate phase, for example, in desalination, gas separation and/or gas sequestration processes. The reactive metal nucleation substrate may include reactive metals from Group II, Group I, or Group XIII of the periodic table, for example, in alloyed form with other metals and/or nonmetal elements.