Nanoporous Silicon-Elastomer Hydrids: From Liquid-Crystalline Functionalization to a Tunable Elasticity Assessed by Laser Ulltrasonics

• Applicant: Professor Dr. Patrick Huber
• Subject Area: Synthesis and Properties of Functional Materials ; Physical Chemistry of Solids and Surfaces, Material Characterisation
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 529978790

Nanoporosity in silicon leads to completely new functionalities of this mainstream semiconductor in numerous fields ranging from nanofluidics and biosensorics to drug delivery, energy storage and photonics. However, a difficult to assess elasticity significantly limited its mechanical exploration and application so far. The ultimate goal of this project is to expand nanoporous silicon’s applications further to the phononic field and to develop a novel hybrid nano-material system with thermally and electrically tunable elastic properties, scalable to industrial needs. The key to achieve this is the combination of wafer-scale nanoporous silicon with liquid crystal elastomers confined in its pores. In order to comprehensively characterize and understand the hybrid’s elastic behavior, we propose to utilize the unparalleled insights provided by in-situ laser ultrasonics and sophisticated computational methods.The assessment of the acoustics will enable the observation of numerous effects: the influence of the pore morphology and porosity gradient orientation on wave propagation, the compressibility of liquid-like, viscoelastic materials in confined spaces and the hybrid’s tuneable elasticity. With complementary advanced X-ray diffraction investigations, we will explore the structure of the liquid crystal elastomers, the role of the confinement and the phase behavior on different stimuli. Ultimately, these insights will allow us to fine tune the material design and synthesis to achieve specific temperature and electric stimulus-dependent elastic properties with potential applications in the field of micro-electro-mechanical systems and in the emerging field of phononics.

• DFG Programme: Research Grants
• International Connection: France
• Cooperation Partners: Professor Nicolas Bochud; Dr. Claire Prada