Hierarchical nanostructured materials through nanoparticle self-assembly.
Nature builds very complex, multifunctional systems by assembling simple building blocks in a directed manner compared to which most manmade structures are relatively simple. In a biomimetic approach, we aim to create hierarchical multi-functional one-, two- and three-dimensional structures with controlled long-range order through self-assembly of multifunctional rodlike nanoparticles. To achieve this, we will modify the surface of rod-like cellulose nanocrystals at their three distinct surface functionalities: primary and secondary hydroxyl groups and aldehydes. Using the difference in reactivity of their lateral surface primary and secondary hydroxyl groups and of the aldehydes located at one cellulose chain end extremity, we will introduce assembly-directing groups, as well as other functionalities such as fluorescence, (electro)chromism, and redox and electron hopping capability. Ordered structures will be formed by self-assembly on solid surfaces, at liquid-liquid and liquid-gas interfaces, in bulk, and under flow, with and without addition of metal nanoparticles or di- or multifunctional linkers. Flexibility and spacing of the grafts will provide additional control over the self-assembly behaviour and performance of the additional functionalities.