High-temperature dielectric responses of molecularly-thin titania nanosheet

We have investigated high-temperature dielectric properties of titania nanosheet (Ti0.87O2), a new class of high-κ nanomaterials derived from the exfoliation of layered compounds. In-situ characterizations using atomic force microscopy indicate a robust insulating property in a monolayer form of Ti0.87O2 nanosheets even at 200°C. Furthermore, layer-by-layer assembled nanocapacitors exhibit both size-free high-εr characteristic (~120) and high insulation resistance (~10−7 A/cm2) at high temperatures up to 250°C. The simultaneous improvement of εr and thermal stability in high-κ nanodielectrics is of critical importance for applications of high-temperature capacitors.