H0 values of counterpart IL cations increased in the following
order: QPS (0.85) N MIMPS (0.88) N TMAPS (0.89) N PyPS (0.91). It
seems that the acidity of POM–ILs as inorganic–organic hybrid materials is affected by intermolecular interactions between IL cations
and PW anion. Van der Waals bonds and electrostatic interactions,
hydrogen bond acidity, the arrangements of IL cations in secondary
structure of POM, and the dispersion force interactions could be varied by changing the IL cations and POM anions and cause to the difference in H0 values.