Review of \mathrm{S}{\mathrm{O}}_{\mathrm{4}}^{\mathrm{2}-}/{\mathrm{M}}_{\mathit{x}}{\mathrm{O}}_{\mathit{y}} solid superacid catalysts

Abstract

Some metal oxides modified with sulfate ions form highly acidic or superacidic catalysts. \mathrm{S}{\mathrm{O}}_{\mathrm{4}}^{\mathrm{2}-}/{\mathrm{M}}_{\mathrm{x}}{\mathrm{O}}_{\mathrm{y}} solid superacid catalysts, play a vital role in more and more fields such as organic synthesis, fine chemicals, pharmaceuticals, and means for strengthening environmental safeguards. This review highlights the recent development of solid superacid catalysts based on \mathrm{S}{\mathrm{O}}_{\mathrm{4}}^{\mathrm{2}-}/{\mathrm{M}}_{\mathit{x}}{\mathrm{O}}_{\mathit{y}}, including synthesis method, characterization of acid sites and acid strength, and applications.

Key words： solid superacid catalyst; synthesis method; characterization; applications

Acknowledgements

The authors would like to thank the National Natural Science Foundation of China (Grant Nos. 20673040 and 20876062) and the Natural Science Foundation of Guangdong Province, China (No. 36055) for financial support of this work.

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