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Creating Value from Non-Carbon 2D Materials

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Creating Value from Non-carbon 2D Materials - Beyond Graphene A state of the art review Contact Graphene and Other 2D Materials SIG www.ktn-uk.co.uk/interests/graphene-and-other-2d-materials Table of contents Executive Summary 5 Glossary of Non-Carbon 2D Materials 7 1. Introduction 8 2. Family of Non-Carbon 2D Materials 11 3. Synthesis and Production of Non-Carbon 2D Materials 15 4. The Innovation Landscape for Non-Carbon 2D Materials 19 5. Strategic Insights for the UK 35 6. Conclusions 42 7. Priorities and Recommendations 43 Acknowledgements 44 References 45 Appendix 1: Examples of R&D and Innovations 46 Appendix 2: Patent Analysis 48 3 4 Martin Good / Shutterstock.com Executive Summary The ability to isolate or grow two-dimensional with specially designed electrical, magnetic, (2D) materials has been a source of scientific piezoelectric and optical functionalities. fascination ever since it was shown to be possible, Research in non-carbon 2D materials has with the isolation of graphene from graphite, benefited from the earlier investments in in 2004 at the University of Manchester. The developing graphene. They can be manufactured increasing range of 2D materials extends far in a similar way and can be combined with beyond graphene and its carbon analogues. It is graphene to address its lack of band gap. Band believed that over five hundred 2D materials have gap is a property that makes silicon and other been developed globally so far. These materials semiconductors so useful for digital electronics. exhibit an exciting range of novel properties, 2D semiconducting materials are likely to become opening the door to a multitude of new potential an attractive choice for constructing digital applications. circuits on flexible and transparent substrates Graphene remains the most famous of for applications such as paper-like transparent these 2D materials, with developments well displays, wearable electronics and photonic advanced. However, research in non-carbon 2D devices. materials is accelerating at a rapid pace with Many application sectors recognise the benefits significant contributions from UK research they can derive from these new materials groups and materials producing SMEs. Clear and have expressed the need to have greater progress has been made with the commercial understanding of the industrial challenges they availability of hexagonal Boron Nitride, h-BN, will face. This led to the KTN undertaking a short and the growing industry interest in transition- project to bring together leading companies and metal dichalcogenides (TMDCs), in particular academics working on 2D materials and devices semiconductor TMDCs such as molybdenum from across the UK. The KTN also met with disulphide (MoS ), which have direct band gap 2 potential industry users and the wider supply and are attractive for optics and optoelectronic chain to explore the challenges faced in bringing devices. There is also a particular excitement these 2D materials to market. The output from about the ability to custom stack thin layers of the project includes this state of the art report, non-carbon 2D materials and, in combination which reviews the current innovation landscape with graphene, create hetero-structured devices. and captures the views of senior academics and These devices have a variety of different electronic industrialists, regarding where the UK should and optical properties, which can be finely tuned be headed to create commercial value from by careful design of the stack. Ongoing research developments in non-carbon 2D materials. is showing great promise for new materials 5 This KTN study has identified a body of work Following considerable discussions with being undertaken globally to develop non-carbon industry experts and academics, the following 2D materials, mainly led by university research recommendations are made to both groups. Companies such as Samsung and IBM government and industry to drive forward the are active in this area, as are UK SMEs such as commercialisation of non-carbon 2D materials in Thomas Swan and 2D-Tech, part of Versarian Plc. the UK. The discussions KTN has had with UK companies 1. Create an Industry Challenge around h-BN suggest that existing businesses developing and TMDCs to accelerate the development of graphene are the ones most likely to look at supply chain and end user partnerships. exploiting other 2D materials. 2. Provide 5-10 years long term funding for The following were noted as the priorities for the centres of excellence to carry out more work UK in our bid to create commercial value from needed in scale-up of non-carbon 2D material current academic research and industry activities: production, device fabrication and end-user • More industry collaboration needed to scale applications. up the manufacturing and use of 2D materials; 3. Invest in scaled-up demonstrators to show and • UK industry to work closely with academic exploit the game changing properties of non- researchers to develop technology roadmaps carbon 2D materials, solely or in combination for mass production and application of 2D with graphene. materials; 4. Consider the overall UK landscape and • Funding needed to improve manufacturing impact of the EU Graphene Flagship project techniques for 2D materials, including device on leveraged funding for development and fabrication and product manufacture. commercialisation activities. 6 Glossary of Non-Carbon 2D Materials CuO Copper oxide SnS2 Tin disulfide h-BN Hexagonal boron nitride SnSe2 Tin diselenide HfS2 Hafnium disulfide TaS 2 Tantalum disulfide LaNb2O7 Lanthanum niobate TiO2 Titanium dioxide MnO2 Manganese dioxide TiS2 Titanium disulfide MoO3 Molybdenum trioxide TiSe2 Titanium diselenide MoS2 Molybdenum disulfide TMDC Transition-metal dichalcogenides MoSe2 Molybdenum diselenide VS2 Vanadium disulfide MoTe2 molybdenum ditelluride VSe2 Vanadium diselenide NbS2 Niobium disulfide WO3 Tungsten trioxide NbSe2 Niobium diselenide WS2 Tungsten disulfide Ni(OH)2 Nickel hydroxide WSe2 Tungsten diselenide ReS2 Rhenium disulfide WTe 2 Tungsten ditelluride ReSe2 Rhenium diselenide ZrS2 Zirconium disulfide RuO2 Ruthenium dioxide 7 1. Introduction Two-dimensional (2D) materials are a new and ability to build custom-made structures (hetero- expanding family of materials with exceptional structures) by stacking combinations of 2D properties. Graphene is currently the most materials on top of each other and constructing famous of these 2D materials, which although one libraries of crystals to provide specific electrical, million times thinner than paper is the strongest thermal, physical or mechanical properties and material known to science. It is made up of carbon functionalities. atoms arranged in a hexagonal lattice and has A number of these non-carbon 2D materials many superlative properties to its credit. The address graphene’s lack of band gap, which is unique combination of superior electrical, optical what makes silicon and other semiconductors so and mechanical properties makes graphene an useful for digital electronics. 2D semiconducting incredible material for diverse applications across materials are likely to become an attractive many sectors. The UK has been a global leader choice for constructing digital circuits on flexible in research on graphene since its isolation from and transparent substrates for applications such graphite crystal at the University of Manchester in as paper-like transparent displays, wearable 2004. electronics and photonic devices. In addition, the The ability to isolate or grow 2D materials has mechanical properties of MoS2 also appear to been a source of scientific fascination ever since be very attractive. It is thought that there may it was shown to be possible. The isolation of be around five hundred 2D materials already graphene has led to the discovery of a whole developed, globally, including graphene. family of 2D materials, including large numbers Research in non-carbon 2D materials has of atomic layers derived from non-carbon 2D benefited from the earlier investments in materials such as hexagonal boron nitride (h-BN) developing graphene with activities in areas and molybdenum disulphide (MoS ). These can be 2 of material structure-property correlations, combined with graphene to create exciting new synthesis and nanofabrication, device integration devices and products. This field is accelerating at and device characterisation studies. a rapid pace and significant contributions have been made by UK researchers. This includes the 8 Many application sectors recognise the benefits Definition of 2D Materials they can derive from these new materials An ISO terminology standard has been developed and have expressed the need to have greater to provide a common definition of 2D materials. understanding of the industrial challenges they It defines 2D materials as “one or several layers will face. This led to the KTN undertaking a short with the atoms in each layer strongly bonded to project to bring together leading companies and neighbouring atoms in the same layer, which has academics working on 2D materials and devices one dimension, its thickness, in the nanoscale or from across the UK. The KTN also met with smaller, and the other two dimensions generally potential industry users and the wider supply at “larger scales”. See ISO/TS 80004-13:2017: chain to explore the challenges faced in bringing ‘Graphene and related two-dimensional (2D) these 2D materials to market. The output from materials’. the project includes this state of the art report,
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