We have recently demonstrated that crystalline layers of graphene can be grown on a solid surface using a newly installed high temperature growth system based on a technique called molecular beam epitaxy (MBE). This system was purchased in 2013 using equipment funding from the EPSRC Graphene Engineering Call and was successfully installed in 2014 and has since been used to demonstrate, for the first time in the world, that graphene which is strained, i.e. stretched, can be grown. It is thought that the stretching arises from the high temperatures used during growth - as the graphene cools after growth it tries to contract but cannot do so since it is pinned at several anchoring points on the surface on which it grows. The presence of strain was completely unexpected and results in many novel properties, for example the graphene can be punctured by a nanoscale mechanical stylus and snap back into a relaxed form - rather like a burst balloon. In addition, it is known that stretching graphene can modify strongly its electrical properties making it more compatible with technological applications such as the fabrication of transistors. In this proposal we are requesting support to build on our initial success so that we can explore the promise of this new type of graphene, to gain a much better understanding of how it grows, to investigate its novel physical properties and also to try and exploit strained graphene to make simple prototype devices. Historically, the discovery of graphene and its remarkable electronic properties by Geim, Novoselov and colleagues in 2004 has provided scientists and engineers with a material system for revolutionising electronics and opto-electronics. Graphene has many remarkable properties - it is highly flexible, very strong and is an excellent electrical and thermal conductor. However, there are some limitations of current graphene research. Firstly, it cannot be used directly in many electronic applications because the flow of electrical current cannot be switched off in graphene, an essential requirement for the fabrication of a transistor, the central component of modern electronics. The reason for this may be traced back to the quantum mechanical properties of electrons within graphene, in particular the fact that for all energies there are available quantum mechanical states which electrons can occupy - in other words the material lacks an energy gap which is present in semiconductors. Since 2004 there has been an enormous effort worldwide to develop methods to control the electronic properties of graphene with a particular focus on introducing a band-gap to provide a semiconducting analogue material in which many of the other, highly desirable qualities of graphene, are retained. One of the most promising routes towards this goal is through the introduction of strain which occurs spontaneously in the MBE grown graphene. In addition, a second drawback of the original graphene work was the reliance on exfoliation, or peeling off layers of graphene from a block of material. Although this has been extraordinarily successful in terms of investigating the fundamental properties of graphene, exfoliation has significant limitations in the technological exploitation of graphene. In particular, it is desirable to form layers over large areas. The approach adopted by the Nottingham group, to use MBE to grow graphene, makes use of a technique which is used widely in industry to grow other materials. However, before the work of the Nottingham group, attempts to grow graphene by MBE, in which growth is achieved by firing carbon atoms at a suitable surface, had been largely unsuccessful. Our system, which is unique worldwide, allows growth of graphene at much higher temperatures than have been used previously and we have already demonstrated that growth of high quality graphene is possible using this technique and offers exciting opportunities for new scientific and technological directions.

Modern technology demands increasingly larger number of new materials to suit the specific requirement of the particular applications. The search for new materials, or even better, for materials with tuneable properties, has dramatically intensified over the last decade. The best strategy here are the composite materials and heterostructures, which allow ultimate tuning of material parameters, combinations of otherwise unmatchable properties and can provide multiple functionalities. However, usually such materials are not readily accessible due to cost and the complex technology required for assembly/production of such structures. Here we propose a new paradigm in creating such composite materials: heterostructures based on 2D atomic crystals, which can be assembled by mass-production means. This way we will decouple the performance of particular devices from the properties of naturally available materials. The ultimate goal is to develop a new paradigm of "materials on demand" with properties precisely tailored for novel complex architectures and structures. The ground-breaking nature of our research and the development of the mass-production technique of the production of such heterostructures will have huge impact on future technology. We will also demonstrate prototypes of multifunctional devices which are based on such a technology. Examples of devices we are planning to create are temperature, humidity, light, strain and many other sensors which will be battery-free and powered by absorbing radio waves (RFID technology, also enabled by printed electronics) for remote sensing applications. Such wirelessly interconnected tuneable sensors and actuators can create a platform for the fast-growing "Internet of Things" paradigm. 2D atomic crystals are one atom thick materials. The family of such crystals is very large and includes transition metal dichalcogenides, hexagonal boron nitride, graphene among many others. Collectively, they cover a large range of properties: from conductive to insulating, from transparent to opaque, from mechanically stiff to compliant. Also, very often the properties of such 2D crystals are very different from the properties of their 3D precursors. Interestingly, many of the unique properties of the 2D crystals are preserved even when we create suspensions (2D inks) out of these materials. Such inks can be used for deposition of the 2D materials to any surfaces, creating low-cost, conformal functional coating. Still, the most important property of materials in this family is the possibility to assemble them into 3D stacks, creating novel heterostructures. Such heterostructures have proven to have new functionalities (tunnelling transistors, LED, etc) or even combinations of several functionalities. The large selection of 2D crystals, ensures that the parameters of such heterostructures can be tuned in a wide range. In this project we propose to develop a low-cost technique to be able to print such heterostructures from 2D inks. Several members of the consortium have already demonstrated that tunnelling diodes, tunnelling transistors and photodetectors can be printed using standard mass-production technologies. We will significantly increase the range of heterostructures produced by such methods, and will specifically concentrate on heterostructures which produce active response (thermo-power, piezoelectric, photovoltaic, etc). Such heterostructures can act as sensors in a number of applications. We will then combine this technology with already developed technique of printing RFID antenna by using graphene inks. This would allow us to create RFID sensors of different types which do not require power source. For instance, we can record temperature of a product or illumination this product has been subjected to. Multifunctional sensors can naturally be achieved with such technique (for instance temperature, strain and humidity could be recorded at the same time).

Membranes offer exciting opportunities for more efficient, lower energy, more sustainable separations and even entirely new process options - and so are a valuable tool in an energy constrained world. However, high performance polymeric, inorganic and ceramic membranes all suffer from problems with decay in performance over time, through either membrane ageing (membrane material relaxation) and/or fouling (foreign material build-up in and/or on the membrane), and this seriously limits their impact. Our vision is to create membranes which do not suffer from ageing or fouling, and for which separation functionality is therefore maintained over time. We will achieve this through a combination of the synthesis of new membrane materials and fabrication of novel membrane composites (polymeric, ceramic and hybrids), supported by new characterisation techniques. Our ambition is to change the way the global membrane community perceives performance. Through the demonstration of membranes with immortal performance, we seek to shift attention away from a race to achieve ever higher initial permeability, to creation of membranes with long-term stable performance which are successful in industrial application.