Effective control of water-interactive states on mesoporous silica films by phosphoric acid addition

The effect of the phosphoric acid addition into the mesoporous silica (MPS) films on the water molecular states was investigated using the infrared spectral separation techniques. When the larger amount of the phosphoric acid was introduced into the MPS films, the surface wettability was changed to hydrophilicity. The interactions between the PO43− and silicate ions would occur to form the phosphoric acid-interacted MPS films, and the surface silanol groups were effectively interacted with the water molecules, indicating the importance of the incorporated phosphoric ions. [Display omitted] •Phosphoric acid-interacted mesoporous silica (PMPS) films were synthesized.•The adsorbed water molecular states were analyzed by infrared absorption spectra.•The wettability was changed to hydrophilicity by the phosphoric acid addition.•The surface silanol groups were effectively interacted with the water molecules.