Advanced physical properties of natural vermiculite clay*

Vermiculite, layered ionic material, belongs to the family of layered silicates. It is very difficult to exfoliate vermiculite into the single sheets, compared to other layered clays with low surface charge, as the surface charge of vermiculite is too high, reaching values between 0.7 – 1.

We present here efficient method of exfoliation of vermiculite crystals into the single sheets, and their physical properties. Vermiculite 1 nm thin single sheets has been examined regarding their composition, conductive, piezoelectric, mechanical and magnetic properties, together with the determination of the band gap value, using XPS, SPM, XRD, magnetic property measurements and EELS.

Determined properties showed that vermiculite is very interesting 2D material for fabrication of 2D heterostructures, promising for combining it with the graphene and other (semi)conductive materials. Moreover, large scale exfoliation process allows large-scale fabrication of the heterostructures by the self-assembly.