Physicists at the University of Bath have developed a flexible process allowing the synthesis in a single flow of a wide range of novel nanomaterials with various morphologies, with potential applications in areas including optics and sensors.
The nanomaterials are formed from Tungsten Disulphide—a Transition Metal Dichalcogenide (TMD) - and can be grown on insulating planar substrates without requiring a catalyst. TMDs are layered materials, and in their two-dimensional form can be considered the inorganic analogues of graphene.
The various Tungsten Disulphide morphologies synthesized—two-dimensional sheets growing parallel to the substrate, nanotubes, or a nanomesh resembling a 'field of blades' growing outwards from the substrate—are possible due to Dr. Zichen Liu's Ph.D. research at Bath to split the growth process into two distinct stages. Through this decoupling, the growth process could be routed differently than in more conventional approaches, and be guided to produce all these material morphologies.
So far, the 'field of blades' morphology has shown powerful optical properties, including strong non-linear effects such as Second Harmonic Generation, that is, doubling the frequency and halving the wavelength of laser light, changing its colour as it does so. The strength of these effects opens up a range of optical applications for the material.
The research is published in ACS Nano.
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