Interfacial water dynamics

Water is the most abundant molecule on earth, indispensable for a plethora of chemical reactions and vital to the functioning of most living organisms. Its seemingly simple three-atomic structure, however, does not intuitively suggest the anomalous behaviour that has been witnessed over the past decades. Interfacial water is particularly interesting to study as its physicochemical properties deviate significantly from the bulk whilst being of crucial importance to both fundamental research and industrial process design.
In this thesis we study the interfacial water dynamics of three highly relevant phenomena by primarily recurring on microfluidics and ultrarapid imaging approaches. The first part focusses on proton diffusion in complex aqueous environments such as the cytoplasm which remains a central issue in the biowater controversy. We evaluate and discuss the relevance of different proton diffusion mechanisms in cellular mimic solutions. The second part of this thesis is centred around droplet formation dynamics which are not only omnipresent in nature and technology, but also constitute a very rich phenomenon involving finite time singularities. We evaluate the outstanding pinch-off behaviour of water and aqueous solutions at the water/air interface that significantly deviates from other comparable non-viscous liquids on the sub-millisecond time scale. In the last part we study a three phase system consisting of water and oil embedded in different ‘rough’ microstructures. Surface topology is identified as important determinant for the relative wettability behaviour of oil and water which constitutes a key finding for the development of efficient and environmentally compatible enhanced oil recovery strategies.