Hydrogels form a special class of form-stable, elastic materials that consist of a (polymer) network and a large amount of water. In this project you will use advanced nonlinear spectroscopic techniques to study biological hydrogels and supramolecular hydrogels. Biological hydrogels have a network formed by protein-polysaccharide chains, and typically contain 90-99% water. These hydrogels are ubiquitous in nature and perform important biological functions. Supramolecular hydrogels contain relatively small molecular components that reversibly assemble via hydrogen bonds and hydrophobic interactions into fibrils or bundels. Supramolecular hydrogels can already be form-stable and elastic while containing an astonishingly large amount (>99.9%) of water. As a result of the non-covalent nature of these interactions, supramolecular hydrogels are highly responsive to external stimuli like changes in temperature, pH, and exposure to light, thus allowing an easy control of their visco-elastic properties. For some supramolecular hydrogels, a small change in temperature already suffices to switch the state of the system between a liquid aqueous solution and a form-stable elastic hydrogel.

In this project you will study the molecular-scale structure and dynamics of the water and the polymer network of biological and supramolecular hydrogels, using femtosecond two-dimensional infrared spectroscopy and polarization-resolved femtosecond infrared spectroscopy. The obtained information will clarify how the macroscopic viscoelastic and responsive properties of hydrogels are determined by the structure and dynamics of the polymer network and the water molecules of the hydrogel.

You have a Masters degree in physics or physical chemistry. Experience with femtosecond lasers and/or nonlinear spectroscopy is a bonus.

The position is intended as full-time (40 hours / week, 12 months / year) appointment in the service of the Netherlands Foundation of Scientific Research Institutes (NWO-I) for the duration of four years, with a starting salary of gross € 2,590 per month and a range of employment benefits. After successful completion of the PhD research a PhD degree will be granted. Several courses are offered, specially developed for PhD-students. AMOLF assists any new foreign PhD-student with housing and visa applications and compensates their transport costs and furnishing expenses.

Ultrafast Spectroscopy

The Ultrafact Spectroscopy group studies the molecular-scale structural dynamics of complex liquids like water and aqueous solutions, and solids (e.g. ice and metal-organic-frameworks). This research is carried out with advanced (nonlinear) spectroscopic techniques including femtosecond  two-dimensional infrared spectroscopy,  vibrational surface sum-frequency generation, and GHz-THz dielectric relaxation spectroscopy.