Plastic electronics, electronic materials that are based on polymers, hold the promise of light weight, low power, cheap, versatile and mechanically flexible electronic devices, applications of which include flexible displays and wearable electronics based on circuits which can be printed using bubblejet printer technology. However, electrically conducting polymers (sometimes called molecular wires, MWs) are often unstable when operated the presence of air or moisture and can deteriorate due to interactions between the polymer chains. These drawbacks currently hinder the development of new commercial plastic electronic devices. One approach which has been developed to help overcome these problems is to wrap the conjugated polymer in an insulating sheath, much as macroscopic wires are insulated using a rubber or plastic coating to prevent degradation and short circuits. These insulated molecular wires (IMWs) can be made by threading the conjugated polymer through the cavity of ring shaped molecules, to create a threaded structure, reminiscent of a bead on a thread, known as a poly-rotaxane (from rota, meaning wheel, and axel). This method has been shown to be extremely beneficial, dramatically improving the stability and properties of the conjugated polymer. However, the existing methods for the synthesis of such poly-rotaxanes are currently extremely limited, hindering the development of these exciting materials. Our proposed research will greatly increase the availability of poly-rotaxane IMWs and will in the long term allow any polymer to be insulated with any macrocycle quickly and efficiently. Ultimately, as a result of the proposed work we will be able to create designer insulated molecular wires to order, potentially revolutionising the use of these novel materials for plastic electronic devices.

Solar photovoltaic (PV) technology is becoming a major source of renewable energy around the globe, with the International Energy Agency predicting it to be the largest contributor to renewables by 2024. This uptake is driven by the building of large PV power plants in regions of high solar resource, and also by the deployment of so-called distributed PV on the roofs of homes and industrial sites. The dominant PV technology to date has been based upon the crystalline semiconductor silicon. The production of silicon PV panels has been commoditised for large-scale manufacturing with costs reducing by a factor of ten in under a decade. Our research addresses the next generation of printed PV technologies which could deliver solar energy with far greater functional and processing flexibility than c-Si or traditional compound semiconductors, enabling tuneable design to meet the requirements of market applications inaccessible to current PV technologies. In particular, we seek to advance photovoltaics based upon organic and perovskite semiconductors - materials which can be processed from solution into the simplest possible solar cell structures, hence reducing cost and embodied energy from the manufacturing. These new technologies are still in the early stages of development with many fundamental scientific and engineering challenges still to be addressed. These challenges will be the foci of our research agenda, as will the development of solar cells for specific applications for which there is currently no optimal technological solution, but which need attributes such as light weight, flexible form factor, tuned spectral response or semi-transparency. These are unique selling points of organic and perovskite solar PV but fall outside the performance (and often cost) windows of the traditional technologies. Our specific target sectors are power for high value communications (for example battery integratable solar cells for unmanned aerial vehicles), and improved energy and resource efficiency power for the built environment (including solar windows and local for 'internet of things' devices). In essence we seek to extend the reach and application of PV beyond the provision of stationary energy. To deliver our ambitious research and technology development agenda we have assembled three world-renowned groups in next generation PV researchers at Swansea University, Imperial College London and Oxford University. All are field leaders and the assembled team spans the fundamental and applied science and engineering needed to answer both the outstanding fundamental questions and reduce the next generation PV technology to practise. Our research programme called Application Targeted Integrated Photovoltaics also involves industrial partners from across the PV supply chain - early manufacturers of the PV technology, component suppliers and large end users who understand the technical and cost requirements to deliver a viable product. The programme is primarily motivated by the clear need to reduce CO2 emissions across our economies and societies and our target sectors are of high priority and potential in this regard. It is also important for the UK to maintain an internationally competitive capability (and profile) in the area of next generation renewables. As part of our agenda we will be ensuring the training of scientists and engineers equipped with the necessary multi-disciplinary skills and closely connected to the emerging industry and its needs to ensure the UK stays pre-eminent in next generation photovoltaics.

Plastic Electronics embodies an approach to future electronics in their broadest sense (including electronic, optoelectronic and photonic structures, devices and systems) that combines the low temperature, versatile manufacturing attributes of plastics with the functional properties of semiconductors and metals. At its heart is the development, processing and application of advanced materials encompassing molecular electronic materials, low temperature processed metals, metal oxides and novel hybrids. As such it constitutes a challenging and far-ranging training ground in tune with the needs of a wide spectrum of industry and academia alike. The general area is widely recognised as a rapidly developing platform technology with the potential to impact on multiple application sectors, including displays, signage and lighting, large area electronics, energy generation and storage, logistics, advertising and brand security, distributed sensing and medical devices. The field is a growth area, nationally and globally and the booming organic (AMOLED) display and printed electronics industries have been leading the way, with the emerging opportunities in the photonics area - i.e. innovative solid-state lighting, solar (photovoltaics), energy storage and management now following. The world-leading, agenda-setting UK academic PE research, much of it sponsored by EPSRC, offers enormous potential that is critical for the development and growth of this UK technology sector. PE scientists are greatly in demand: both upstream for materials, process and equipment development; and downstream for device fabrication and wide-ranging applications innovation. Although this potential is recognised by UK government and industry, PE makes a major contribution to the Advanced Materials theme identified in Science Minister David Willet's 'eight great technologies', growth is severely limited by the shortage of trained scientists and engineers capable of carrying ideas forward to application. This is confirmed by industry experts who argue that a comprehensive training programme is essential to deliver the workforce of scientists and engineers needed to create a sustainable UK PE Industry. The aim of the PE-CDT is to provide necessary training to develop highly skilled scientists and engineers, capable both of leading development and of contributing growth in a variety of aspects; materials-focused innovation, translation and manufacturing. The CDT brings together three leading academic teams in the PE area: the Imperial groups, with expertise in the synthesis, materials processing, characterisation, photonics and device physics, the Oxford team with expertise in ultrafast spectroscopes probes, meso and nano-structured composites, vacuum processing and up scaling as well as the material scientists and polymer technologists at QMUL. This compact consortium encompasses all the disciplines relevant to PE, including materials physics, optoelectronics, physical chemistry, device engineering and modelling, design, synthesis and processing as well as relevant industrial experience. The programme captures the essentially multidisciplinary nature of PE combining the low temperature, versatile manufacturing attributes of plastics with the functional properties of semiconductors and metals. Yet, to meet the needs of the PE industry, it also puts in place a deep understanding of basic science along with a strong emphasis on professional skills and promoting interdisciplinary learning of high quality, ranging across all areas of plastic electronics.

The twentieth century saw an explosion in semiconductor electronics from the first transistor, which was used in hearing aids, to the ultrafast computers of today. A similar surge is anticipated for Plastic Electronics based on a new type of semiconducting material which is soft and flexible rather than hard and brittle. Plastic Electronics is considered a disruptive technology, not displacing conventional electronics, but creating new markets because it enables the printing of electronic materials at low temperatures so that plastic, fabric, paper and other flexible materials can be used as substrates. Printing minimises the waste of materials and low cost roll-to-roll manufacturing can be used because the substrates are flexible. New applications include intelligent or interactive packaging, RFID tags, e-readers, flexible power sources and lighting panels. The organic field effect transistor (OFET) is the fundamental building block of plastic electronics and is used to amplify and switch electronic signals. The organic semiconducting channel connects the source and drain electrodes and is separated from the gate electrode by an insulating dielectric. A positive/negative gate voltage induces negative/positive charges at the insulator/semiconductor interface and so controls the conductivity of the semiconductor and consequently the current flowing between the source and drain. The future success of the industry depends on the availability of high performance solution processable materials and low voltage device operation. The semiconductors must have high electron and hole mobility (velocity/electric field) achieved by the hopping of carriers between closely spaced molecular sites. A new class of lamellar polymers, mostly developed in the UK, provides the required state-of the art performance because of their macromolecular self-organisation. However a major problem is that the materials are only well-ordered in microscopic domains; trapping in grain boundaries and poor interconnectivity between domains substantially reduce performance and reliability. The low voltage operation of OFETs requires that the gate insulators have a high dielectric constant. We propose novel insulating dielectrics for OFETs to simultaneously align the plastic semiconductors and ensure low voltage operation. They will be solution processable at low temperatures for compatibility with printing and other large area manufacturing techniques. We will synthesise and characterise the new materials and test their performance using state of the art semiconductors. We will engage with industrial end-users to ensure that our technology is exploited so contributing to the high-tech economy in an area where the UK is already pre-eminent. We anticipate that our novel insulators will provide monodomain order over large areas to the overlying semiconductor and so will enhance OFET performance and stability. Hence we aim to hasten the commercialisation of Plastic Electronics.