Radiant 2-dimensional carbon nitride nanomaterials
2-dimesional carbon nitride nanomaterials that could be used to create light emitting diodes (LEDs) or solar cells have been made through the simple, but unconventional, method of spontaneous dissolution.
This new industrially-scalable approach, published in Nano Letters, produces solutions containing fluorescent solutes that are defect-free, hexagonally-shaped 2d nanosheets. The production method is in stark contrast to the standard alternatives, which rely on high energy input to delaminate layered materials, to produce meta-stable dispersions of fragments of 2d materials rather than pristine nanosheets.
Figure: Hexagonal carbon nitride nanosheets gently dissolve into solution over time (left), producing luminescent, defect free 2d-nanosheets (right)
The team from the LCN, as well as the UCL departments of Chemistry and of Physics & Astronomy, Imperial College London, the University of Bristol and the École Polytechnique Fédérale de Lausanne, used advanced atomic force microscopy and transmission electron microscopy to investigate the structure 2D nanomaterials.
carbon nitride nanomaterials
“Our method is surprising but incredibly simple. When we added certain solvents the layers of the carbon nitride simply floated off into solution. The process is very gentle so that the hexagonal shape of layers is maintained. Our high resolution TEM shows there are no visible defects across the entire sheets” said Dr Thomas Miller , UCL Chemistry.
In the study, funded by the European Union’s Graphene Flagship and the Engineering and Physical Sciences Research Council, the scientists showed that when these solutions were illuminated with UV light, they glowed (luminesced) with a distinctive colour. They went on to discover that this colour could be tuned by controlling the number of nanosheets stacked on top of one another.
The carbon nitride nanosheets are the latest 2d materials that the researchers at UCL can create by the scalable, non-damaging technique of spontaneous dissolution. They recently showed that many 2d materials could be made by dissolving salts of their bulk 3d analogues. However, for this new material they found that the first step was not needed and the nanosheets dissolved from the bulk in their as-synthesised form.
“The work is part of our ongoing research demonstrating that in some cases carbon nitride nanomaterials can be thermodynamically driven into liquids to form true solutions (similar to table salt dissolving in water), as opposed to the traditional view that nanomaterial dispersions are always meta-stable colloidal suspensions” explained Dr Chris Howard, LCN & UCL Physics & Astronomy.
UCL Business PLC (UCLB), the technology commercialisation company of UCL has patented this research and will be supporting the commercialisation process.
Link to publication: ‘Single Crystal, Luminescent Carbon Nitride Nanosheets Formed by Spontaneous Dissolution’ by Thomas S. Miller, Theo M. Suter, Andrew M. Telford, Loren Picco, Oliver D. Payton, Freddie Russell-Pavier, Patrick L. Cullen, Andrea Sella, Milo S. P. Shaffer, Jenny Nelson, Vasiliki Tileli, Paul F. McMillan and Christopher A. Howard
Related link: UCL News, New solution for making 2D nanomaterials
About The London Centre for Nanotechnology
The London Centre for Nanotechnology is a UK-based multidisciplinary enterprise operating at the forefront of science and technology. Our purpose is to solve global problems in information processing, healthcare, energy and environment through the application of nanoscience and nanotechnology. Founded in 2003, the LCN is a joint venture between University College London and Imperial College London and based at the Bloomsbury and South Kensington sites.
The LCN occupies a purpose-built eight storey facility in Gordon Street, Bloomsbury (opened in 2006) as well as extensive facilities within different departments at South Kensington. The Centre’s experimental research is supported by leading edge modelling, visualisation and theory through its access to state-of-the-art clean-room, characterisation, fabrication, manipulation and design laboratories.
The Centre has a unique operating model that accesses and focusses the combined skills of both universities across several key departments; Chemistry, Physics, Materials, Medicine, Electrical and Electronic Engineering, Mechanical Engineering, Chemical Engineering, Biochemical Engineering and Earth Sciences.
The LCN also has strong relationships with the broader nanotechnology and commercial communities and is involved in many major collaborations. As the world’s only such facility located in the heart of a metropolis, the Centre has superb access to corporate, investment and industrial partners. It is at the forefront of nanotechnology training and enjoys a strong media presence around educating the public and bringing transparency to this far-reaching and emerging science.
The LCN building was opened in 2006 after 4 years planning and construction. It was formed as a result of several key academic and scientific considerations in the early part of the millennium… read more
A full range of Facilities and Operations Management functions are undertaken within the LCN to ensure that a critical infrastructure is maintained to fully support the needs of the research… read more
The LCN is jointly owned and run by UCL and Imperial, with one co-director from each. They operate under the stewardship of a Board of Directors and an Executive Board… read more