Project Details
Projekt
Hierarchically structured porous ceramics and composites from nanocasting of plant cell walls
Subject Area
Materials Science
Term
from 2009 to 2015
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 127630356
The achieved successful replication of plant tissue into anisotropic silica and earth alkaline carbonates led to materials with a hierarchical and directional porosity which show promising application potentials in several fields. Within the last funding period of the SPP, two of the most promising directions towards functional (part 1) and structural (part 2) engineering materials are followed. In the first project part, we investigate the prerequisites for the humidity controlled macroscopic movement of plant tissues and the transfer of this functional property into an inorganic material using our nanocasting replication process. First, we will study and model the actuation of native pine cone scales (Pinus resinosa) in order to understand the displacement characteristics of the involved tissues. Second, we will optimize the transfer of the anisotropy and preservation of the hierarchical structures of the pine cone scales into the inorganic composite material. This will allow us to correlate the actuation of the replicated inorganic materials with the one of the native scales. As a result, we will be able to develop mechanical models that describe the deformation mechanisms at the nanometre scale and the resulting macroscopic actuation mediated by the hierarchical structure. It is a major aim to understand how the presumed fundamentally different molecular deformation mechanisms lead to similar macroscopic actuation, and how this is related to the hierarchical architecture of the tissue. For this, we also plan to build a simplified inorganic stimuli-controlled actuation device from anisotropically patterned cellulose gels, whose actuation performance can be directly compared with the mechanical models. In the second project part, the replication of plant tissue as amorphous or nano-crystalline mineral phases other than silica is envisioned to reproduce nanoscale structure and to achieve anisotropic mechanical properties of relevant construction materials. One aim is to employ alternative routes to obtain amorphous alkaline earth metal carbonates (also other than Ca) so that the mechanical stability can be improved. In a significant further development within this project part, we will investigate the formation of the complex amorphous mineral phase calcium silicate hydrate (C-S-H) within the hierarchical structure of plant tissues or within silica replicas. Our primary goal here is to grow such C-S-H-phases within the nanopores of a silica wood replica, which will provide fundamental insights into the formation of C-S-H phases in the confined geometry of nanopores. Utilizing different synthesis methods, we further want to prepare C-S-H fibre reinforced wood and wood replicas, which after calcination yield transparent calcium silicate glasses. A translucent calcium silicate replica of a plant material would be most fascinating in construction applications, because it would combine light transmittance and heat/sound insulating properties.
DFG Programme
Priority Programmes
Subproject of
SPP 1420:
Biomimetic Materials Research: Functionality by Hierarchical Structuring of Materials
International Connection
Austria
