Chemistry and physics of conjugated coordination nanosheets and two-dimensional conjugated polymers

The optoelectronic properties of conjugated polymers have improved to levels of performance that now enable industrial applications in large-area electronics, displays, bioelectronics and photovoltaics. However, the one-dimensional (1D) nature of charge transport along the backbone of a conventional conjugated polymer still imposes fundamental limits on the achievable charge carrier mobilities and electronic properties. In the proposed project we aim to develop a novel class of 2-dimensional (2D) conjugated polymers and coordination nanosheets (CONASHs), which have recently become synthetically accessible through coordination chemistry and promise to overcome the traditional limitations of 1D polymers. The aim of the proposed project is to investigate the fundamental chemistry and physics of these novel materials, in particular investigate the molecular structure - charge transport relationships, explore their fundamental, exotic physical transport properties and develop them as high performance materials for energy and electronic applications, in particular in thermoelectrics, energy storage, light-emission and chemical and biological sensors. The project will establish a close, interdisciplinary network between internationally leading chemistry and physics groups in this field (Nishihara - University of Tokyo, Sirringhaus -University of Cambridge, Feng - Technical University of Dresden, Zhu/Zhang - Chinese Academy of Sciences, Beijing).

In contrast to other 2D materials such as graphene or metal chalcogenides coordination nanosheets can be grown in a controlled manner by a bottom-up chemical synthesis reacting metal ion precursors and organic molecules that progresses under mild conditions and gives access to a wide variety of chemical structures and porous geometric structures by combining different metal ions and organic ligands. This allows tailored design of materials for specific physical, chemical and mechanical properties. These materials exhibit very interesting physical and chemical properties, including redox, photo and catalytic functionality, and might even exhibit exotic physical properties, such as topological insulator behavior. The chemistry, physics and electronics of these materials is a rapidly expanding international research field and the future development of these materials would greatly benefit from a close international research collaboration that is the aim of this proposal. In the proposed research exchange we will advance the development of CONASHs and 2D polymers by bringing together leading international researchers from different disciplines across chemistry, physics and materials science. We see significant potential for creating a new functional materials platform with enhanced levels of device performance for a broad range of applications, including electronics, optoelectronics, energy storage, thermoelectrics as well as chemical and biological sensing.

While the focus of the network is primarily on academic collaboration all five senior investigators have extensive experience in collaborating with industry and in exploiting opportunities for transfering fundamental materials inventions to industry. Prof. Sirringhaus, for example, is cofounder and Chief Scientist of Plastic Logic/FlexEnable, a spin-off company commercialising flexible electronics, and cofounder of Eight 19, which is commercialising organic solar cell technology. The five senior investigators will continuously monitor and assess potential application opportunities for conjugated coordination nanosheets and 2D conjugated polymers and will take appropriate steps to protect arising intellectual property. For this the partners will enter into a collaboration agreement that will set out the terms for filing and exploitation of intellectual property generated within the network. After protection of the IP they will explore different commercialisation paths, including collaboration with industrial companies or the formation of spin-off companies. All four partners have effective technology transfer organisations, such as Cambridge Enterprise at the University of Cambridge, which will work together and follow best practice in commercialisation when such opportunities arise.

The most important impact from the project is however likely to be the training of a cohort of young scientific researchers who will learn to undertake interdisciplinary and collaborative science at the highest international level. Many of these young researchers will in due course lead their own research initiatives and will become proponents of an open science system that seeks to advance scientific knowledge effectively by making optimum use of complementary skills available in different countries and institutions and to share scientific knowledge widely for the benefit of mankind.