Inorganic, non-metallic materials exhibit interesting passive and active mechanical properties, when structured hierarchically down to the nanometer scale by biotemplating. While nature does provide a great wealth of structural templates, tailoring biotemplated materials' architectures on defined hierarchical levels is a desirable goal.
We combine biotemplating techniques, developed earlier,[1,2] with two novel approaches to create tailored templates, namely the utilization of microbial phototaxis, and rheotaxis. These are the alignments of microbes in relation to light patterns, and fluid streamlines.
The generally uncommon ductilities of biotemplated, hierarchically and anisotropically structured silica materials were determined and traced via a stick-slip model of parallel rods. Further, we observed passive moisture-driven bilayer actuation in silica structures derived from actuating biological templates, illustrating one of the attainable novel properties.
With regard to the creation of tailored templates, the directions, velocities and patterns of movement of a selection of microbe species were found to depend on illumination brightness, wavelength, direction, and also the culturing conditions. We also found that flagellated microbes can be induced to manipulate structure-forming particles by light guidance.
We confirmed that unique mechanical behaviors are achieved by templating hierarchically structured biological materials.[3-5] We identified promising pathways to pattern complexly structured, hierarchical materials using live microbes. Patterning them into complex shapes can be achieved via computer-controlled illumination in a defined plane.
 D. Van Opdenbosch, G. Fritz-Popovski, O. Paris, and C. Zollfrank, J. Mater. Res., vol. 26, no. 10, pp. 1193–1202, 2011.
 G. Fritz-Popovski, D. Van Opdenbosch, C. Zollfrank, B. Aichmayer, and O. Paris, Adv. Funct. Mater., vol. 23, no. 10, pp. 1265–1272, 2013.
 G. Fritz-Popovski, R. Morak, T. Schöberl, D. Van Opdenbosch, C. Zollfrank, and O. Paris, Bioinspired, Biomim. Nanobiomaterials, vol. 3, no. 3, pp. 160–168, Sep. 2014.
 D. Van Opdenbosch and C. Zollfrank, Adv. Eng. Mater., vol. 1801097, p. 1801097, 2019.
 D. Van Opdenbosch, G. Fritz-Popovski, W. Wagermaier, O. Paris, and C. Zollfrank, Adv. Mater., vol. 28, no. 26, pp. 5235–5240, 2016.