Novel microporous solid “Superacids”: CsxH3−xPW12O40 (2≤x≤3)

It was confirmed that pore size of the acidic Cs salts (CsxH3−xPW12O40) was controlled by the Cs content. For example, Cs2.5H0.5PW12O40 had mesopores and micropores larger than 8.5in diameter, and Cs2.2H0.8PW12O40 micropores of about 7 . Shape selective catalysis was clearly observed for the latter catalyst. The acidic Cs salts as well as H3PW12O40 possess very strong acidity and were more catalytically active than zeolites and SO42−/ZrO2 for decomposition of esters and alkylation in liquid-solid reaction system.