Clathrate Hydrates as a Kind of Promising Ice Nanoreactors

Since their discovery, clathrate hydrates (CHs) have received great attention both from theoretical and experimental aspects due to their great potential for gas storage and prospective applications as icy crystal materials. However, there has been limited research on the decomposition, reduction or other reactions of gases enclosed in CHs. Thanks to their unique hydrogen bonding network and cavity structures, CHs can serve as the promising nanoreactors to achieve chemical conversions, e. g. reducing greenhouse gases. In this review-type article, we characterize the potential performance of such CHs nanoreactors by discussing their multiple functions including important roles of hydrogen bonds in CHs, e. g. the confinement effect and proton source, and then discuss the enhanced electron-binding ability of guest molecules and the structures and properties of trapped electrons in the stacked nanocages, which contribute to our understanding of chemical reactions occurring in CHs. Finally, we provide detailed analyses of representative reaction mechanisms underwent in CH nanoreactors and effective calculational and molecular dynamics simulation methods. This review-type article aims to provide a detailed summary about the functional characteristics of CHs and reactivity in CHs, which make CHs a kind of promising icy nanoreactors.