Abstract: EuRu codoped NiOSnO2 composite nanoparticle thin films were prepared using solhydrothermal spincoating method. The film structural and electrical properties were characterized by transmission electron microscopy， atomic force microscopy and currentvoltage measurements. The results indicate that the film surfaces are flat and smooth with average roughness of about 025nm. The data of Miller indices and interplanar spacings from the selected area electron diffraction are consistent with that from the XRD card of NiO or SnO2， and the hydrothermal mechanism also shows that nanoparticles are composed of microscale pn junctions of NiOSnO2. The nanoparticle films exhibit reproducible resistive switching with threshold voltage of about 1V and on/off ratio of 500. The currentvoltage measurements indicate that the conduction is governed by the Ohmic law for the low resistive state， while the high resistive state is dominated by the space charge limited conduction. The switching mechanism can be ascribed to the charge trapping/detrapping process induced by the applied threshold electrical field.

Key words: solhydrothermal method, NiOSnO2 composite nanoparticles, resistive switching, charge trapping/detrapping, EuRu codoping