Hope, M.A., et al., Surface-selective direct 17O DNP NMR of CeO2 nanoparticles. Chem Commun (Camb), 2017. 53(13): p. 2142-2145.
Surface-selective direct 17O DNP has been demonstrated for the first time on CeO2 nanoparticles, for which the first three layers can be distinguished with high selectivity. Polarisation build-up curves show that the polarisation of the (sub-)surface sites builds up faster than the bulk, accounting for the remarkable surface selectivity.