Few-layered-graphene/zirconia composites: Single-step powder synthesis, spark plasma sintering, microstructure and properties

•Few-layered-graphene (FLG) films of very homogeneous thickness have been deposited on the surface of the grains of a 3YSZ ceramic powder.•A high level of densification of these composite materials has been achieved by using the Spark Plasma Sintering process.•FLG's high levels of distribution at grain boundaries result in electrically conductive materials with less than 1.98 vol.% carbon content.•Materials with anisotropic electrical conductivity (ratio σ⊥ / σ// about 4) are obtained.•The toughness of composites increases with the carbon content suggesting a slight reinforcing role of the FLG.