The laboratories were adapted to the project requirements. The research instruments were acquired and tested. The doctoral students working on the project were hired, so that the starting configuration of the team was ready. In our research, various types of nanoparticles differing in size, shape and composition could be synthesized. We have characterized them by optical spectroscopy, electron microscopy and electrochemically. We were able to synthesize also previously unknown nanoparticles with new physicochemical properties. The nanoparticles are the building blocks for our gels, which can be seen as self-supporting networks from these nanoparticle building blocks extending to the macroscopic size regime. Our research therefore included the investigation of possibilities to form such networks - gel formation routes. Various gel formation routes were tested and new ones developed, and depending on the respective building blocks, the best gelation routes were selected to form such macroscopic gels. One of the gelation routes developed by our group is easily applicable to all types of aqueous solutions of nanoparticle building blocks. In this route, directly aerogels are synthesized without the need of so-called supercrytical drying (the transfer from liquid to gas environment, which is sometimes technically challenging). It was also shown that by simple freezing and subsequent thawing, so-called cryohydrogels can be made directly, so that for aqueous applications no drying and re-hydratization is necessary, which increases the mechanical stability of the gels. We have found out that this new gelation technique is also suitable for making aerogels from two different components of nanoparticles. Our investigations show that we can even control the microscopic distribution of the two components within the aerogels by controlling the nanoparticle surface chemistry. Another important novelty is that all possible mixing ratios of the two components are possible. In recent works we have shown that the physical properties of gels differ significantly even from the same nanoscopic compositions if the structure differs: The nature of the contact between different nanoscopic domains is of utmost importance, as well as the nano- and microscopic distribution of the compounds. Additionally we have conducted spectroelectrochemical and various optical investigations how far generated charge carriers can travel in gels. Of the new gels developed, we were able to investigate the new physical and chemical properties, e.g. by elecron microscopy and spectroscopic as well as spectroelectrochemical techniques. Further works concentrated on developing shaping methods of the gels by means of inkjet printing, additive manufacturing and molding. In several publications, the main results achieved were described and discussed in detail.
