A nanocomposite including a metal oxide and two-dimensional nanosheets. The metal oxid includes at least one of zirconia and titania, and the two-dimensional nanosheets include at least one of reduced graphene oxide and boron nitride. A weight ratio of the metal oxide to the two-dimensional nanosheets is in a range of 2:1 to 19:1, or in a range or 2:1 to 9:1. Making the nanocomposite includes forming a first aqueous dispersion including zirconia nanoparticles and graphene oxide powder, combining a reducing agent with the first aqueous dispersion, irradiating the first aqueous dispersion with microwave radiation, thereby yielding a second aqueous dispersion including zirconia and graphene, and separating the nanocomposite from the second aqueous dispersion, wherein the nanocomposite comprises zirconia and graphene.