High-Field 17O MAS NMR Investigation of Phosphonic Acid Monolayers on Titania

摘要: High-field 17O MAS NMR was used to investigate the binding of self-assembled monolayers 17O-enriched phosphonic acids deposited on a titania anatase support. The spectra were recorded at two different magnetic fields (9.4 and 17.6 T), improve reliability simulations resonances. T offer an excellent resolution between oxygen sites, P═O, P−O−H, P−O−Ti, thus greatly facilitating their quantification. data reported here give direct evidence extensive formation Ti−O−P bonds in surface modification by acids. presence residual P═O P−O−H sites indicates several modes acid monolayers. chemical shift P−O−Ti is consistent with bridging (as opposed chelating) modes.