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Hierarchical Assembly in Controllable Matrices

Final Report Summary - HIERARCHY (Hierarchical Assembly in Controllable Matrices)

The scientific goal of the Hierarchy project was to control self-assembly on multiple length scales. Self-assembly is the process where molecules organise into functional larger structures, a well-known concept in Nature. Scientists, for a long time, have considered self-assembly a natural way forward in the continuously miniaturising world and major steps forward have been reported. In time, it has, however, proved difficult to order these, still very small, structures to include them in devices. Hierarchy aimed to control the assembly properties beyond the few nanometres, but on device dimensions.
To target this problem seven academic institutes and three industrial partners (1 SME, 2 large industries) from four European countries joint forces and hired nearly thirty early stage (ESR) and experienced (ER) researchers.
The central approach in Hierarchy was the use of liquid crystalline media to template the self-assembly process. Liquid crystals are well-known from the display industry and the required electro-optical properties have been studied and described in detail. In Hierarchy, this new concept was demonstrated in different fields of application: confined reactors (Work Package 2); photonic crystals (WP3) and Bio-sensing (WP4). Work package 1 comprised the training of young scientists in quickly developing field of nanosciences in general, with a focus on hierarchical structures. This summary discusses the results from the individual work packages.
WP1: Training. Hierarchy hired for training and research 29 young academics (41% female) from countries all over the world (approx. 31% EU; 215 associated countries; 48% third countries). Recruitment at the start of the project was rather slow. To fulfil the requested training months as good as possible, recruitment intensified at the later stage of the project. The Network supplied to the fellows 607 ESR training months (applied: 648 months) and 111 ER training months (applied: 108 months). Over 95% of the applied training moths have been delivered. Of the 29 fellows working for the network, more than 40% were woman, underlining the move towards gender equality in natural sciences.
At the start of their training, the ESRs and ERs were asked to draft, together with their supervisors, a career development plan (CDP) that comprises a plan for training during the fellowship as well as a further career planning. The CDP is reviewed by the fellow and the supervisor to allow for adjustments as the individual programmes develop. The CDPs were also discussed at a central level with the Network’s training coordinator.
The training of each fellow was organised in two parts: Training provided by the host institute and training provided by the Network. The latter consisted of four two-day training modules, training modules to develop entrepreneurial skills and a winter school, an international conference organised by Hierarchy and a number of Network progress meetings. In the latter meetings, the fellows presented their work to a specialised, but very broad audience, which directly trained their presentation. In addition, at these meetings they came into contact with the other fellows and supervisors of the project, which on many occasions initiated collaborations.
The collaboration is one of the excellent results of Hierarchy: starting with a group of individual institutes and companies, during the project, an international team of scientists developed with many collaborations and cross-fertilisations. The secondments, mandatory for all fellows in the project, also helped to develop or, once established, strengthen the collaboration. In that respect, the partners (and the fellows) strongly benefitted from the strongly inter-sectorial and interdisciplinary character of the Network. In addition, two visiting scientists, both experts in the field, interacted with the fellows to broaden their perspectives.
The goal of WP2 (Confined Reactors) was two-fold: (1) develop the materials necessary for the rest of the project (when not available commercially) and (2) apply the tools and science of the materials development to confined reactors. Different methods to generate nanostructures with molecular and larger scale organisation have been investigated, using liquid crystalline and block-copolymer scaffolds. The work, for instance, resulted in different anisotropic networks with potential application in new sensing platforms, targeting small molecules to proteins or even larger biostructures, in anisotropic nanoparticles with highly interesting optical properties. The scientific efforts in this work package have also resulted in commercial potential, highlighted by patent applications in this field by one of the partners. Collaborative projects between different continued after Hierarchy ended.
In WP3 (Photonic Crystals), the goal was to develop nematic colloids for optical applications. These hierarchical materials provide great approaches to new and tuneable photonic materials. The goal of this work package was not only to make and characterise the devices, but also to model them, to allow for better future designs. Particular attention was paid to the generation of Hierarchical structures of particles of different length scales and to lattices in three dimensions. These goals have been accomplished and this has resulted in some academic rewards (papers in Sience, Nature Photonics, Nature Communications amongst others), commercial activity (patent applications) and the development of products (welding masks).
WP4 (Biosensing) was geared towards using the anisotropic systems in sensing applications, where the focus was more on developing new sensing platforms than developing a demonstrator. Different materials are developed (also in WP2) in parallel with a major difference between them the length scales of the materials. Hydrogels with pore sizes of 2 nm to 200 nm were inversigated. The work has generated many results , too many to summarise here. A certain highlight is the preparation and full characterisation of a completely biomimetic gel (published in Nature). The development of fully flexible microfluidic technology by Philips was used by multiple partners in this WP to integrate their technology to existing lab-on-a-chips sensing technology. Also in this work package several patent were filed.
At the end, researchers in Hierarchy produced over 100 peer-reviewed papers on Hierarchical assembly and very closely related topics, some of them in truly excellent journals, like Nature, Science, Nature Materials etc. Moreover, the science developed in Hierarchy is also commercialised. This is demonstrated by the application for 8 patents in the network as well as the full commercialisation of a product (large area shutters for welding masks), which is the best among its peers.