Chemical transformations carried out in water (or a water-rich fluid) above ambient temperature under the autogenous pressure of the closed vessel constitute hydrothermal synthesis. The solvent is superheated water, whose decreased permittivity, altered ion product, and enhanced solubility of inorganic species enable dissolution–reprecipitation and crystallization pathways that are inaccessible in open aqueous solution. Hydrothermal crystallization is the defining industrial and laboratory route to many zeolites, in which aluminosilicate gels reorganize into microporous frameworks [1]. Controlled hydrothermal growth produces ZnO nanorods with a defined diameter regime [2]. Selective control of hydrothermal conditions can also determine whether α- or β-MnO2 single-crystal nanowires form [3]. The concept is a synthetic method specified by the aqueous, high-temperature, closed-system medium, not by a single product class: molecular organic reactions, carbonized polymer dots, and inorganic crystals can all be formed hydrothermally. Solvothermal synthesis is the analogue in nonaqueous solvents. Ambient-pressure aqueous precipitation and dry solid-state calcination lie outside the term.
- hydrothermal synthesis
- aqueous crystallization
- autogenous pressure
- inorganic nanostructures
Synthesis and Catalytic Reactions • Organic Chemistry • Chemistry • Physical Sciences
References
- Colin S. Cundy; Paul A. Cox; The Hydrothermal Synthesis of Zeolites: History and Development from the Earliest Days to the Present Time. Chem. Rev. 2003, 103, 663-702, 10.1021/cr020060i.
- Bin Liu; Hua Chun Zeng; Hydrothermal Synthesis of ZnO Nanorods in the Diameter Regime of 50 nm. J. Am. Chem. Soc. 2003, 125, 4430-4431, 10.1021/ja0299452.
- Xun Wang; Yadong Li; Selected-Control Hydrothermal Synthesis of α- and β-MnO2 Single Crystal Nanowires. J. Am. Chem. Soc. 2002, 124, 2880-2881, 10.1021/ja0177105.