Enhancement of critical current density of YBa2Cu3O7−δ thin films by nanoscale CeO2 pretreatment of substrate surfaces

YBa2Cu3O7−δ (YBCO) films were prepared on single-crystal SrTiO3 substrates with metal–organic deposition using trifluoroacetates (TFA-MOD). Positive results have been acquired in controlled study to investigate the effects of substrate surface modification on the growth-induced flux-pinning nanostructures in YBCO films. Nanoscale CeO2 particles were applied to single-crystal SrTiO3 substrate surfaces using pulsed laser deposition before YBCO precursors coating. Superconducting properties of the YBCO films grown on the controlled CeO2-modified substrates have shown substantial improvement in the critical current densities (Jc) at 77 K over those grown on untreated substrates in almost all the field (78% increment at 1 T, 77 K). We think the reason is that the CeO2 nanoparticles act as pinning centers.