Optoelectronically-active two-dimensional indium selenide and related layered materials via surfactant-free deoxygenated co-solvent processing
Preparation of two-dimensional indium selenide, other two-dimensional materials and related compositions via surfactant-free deoxygenated co-solvent systems.
1. A method of preparing a layered nanomaterial, said method comprising:
providing a composition comprising a bulk layered material exfoliatable into a layered nanomaterial, and a surfactant-free deoxygenated co-solvent system comprising ethanol and water, wherein said co-solvent system is 60:40 (v/v) ethanol:water, and said composition is substantially absent of a surfactant;
sonicating said composition to provide said system comprising exfoliated nanomaterials; and
centrifuging said system to provide a supernatant component comprising at least one of mono-, bi- and n-layer nanosheets of said nanomaterial dispersed therein, where n is an integer selected from 3 to 6,
wherein said bulk layered material is selected from transition a metal dichalcogenide, a Group III monochalcogenide, a Group IV monochalcogenide, hexagonal boron nitride, graphene, and black phosphorus; and
wherein said transition metal dichalcogenide is selected from MoSe 2 , MoTe 2 , WS 2 , and WSe 2 .
2. The method of claim 1 , wherein the speed of centrifugation selectively provides said nanosheets of a thickness dimension.
3. The method of claim 1 , wherein said co-solvent system comprises an Ar-purged co-solvent mixture of ethanol and water.
4. A method of preparing a layered nanomaterial, said method comprising:
providing a composition comprising a bulk layered material exfoliatable into a layered nanomaterial, and a surfactant-free deoxygenated co-solvent system comprising ethanol and water, wherein said co-solvent system is 60:40 (v/v) ethanol:water, and said composition is substantially absent of a surfactant;
sonicating said composition to provide said system comprising exfoliated nanomaterials; and
centrifuging said system to provide a supernatant component comprising at least one of mono-, bi- and n-layer nanosheets of said nanomaterial dispersed therein, where n is an integer selected from 3 to 6,
wherein said bulk layered material comprises a Group III monochalcogenide, and wherein said Group III monochalcogenide is InSe.