Friday, 2 August 2024 11:00am – 12:00pm

This seminar will be delivered in Lecture Theatre 3

Speaker: Professor Alberto Giacomello

Host: Professor Chiara Neto

Title: Understanding water behaviour in hydrophobic nanopores for energy, chromatography, and biomimetic applications

Abstract: In hydrophobic nanopores, extreme confinement may induce water evaporation at ambient conditions [1]. Such exotic phase behaviour plays a crucial role in biological phenomena such as hydrophobic gating and in nanotechnology, including nanoporous materials for energy [2], chromatography [3] and single-nanopore technologies [4]. In this talk, theory and simulation will shed light on the thermodynamics and kinetics of evaporation in nanopores and on their dependence on the hydrophobicity, geometry, size, and elasticity of the pores. Controlling such phenomena opens the door to engineered hydrophobic nanoporous materials which, immersed in water, can store or dissipate energy, realising highly compact mechanical batteries or vibration dampers [2,3]. In the realm of high-performance liquid chromatography, such knowledge is helpful for preventing retention losses by dewetting [3]. The importance of evaporation induced by confinement in biology will also be discussed, where the “gating” of ion currents across the cellular membrane through specialised proteins, the ion channels, may rely on the formation of a nanoscale bubble within the hydrophobic pore [5]. Biomimetic hydrophobically gated nanopores display memristive properties to be used in neuromorphic applications [4]. Finally, the interplay of elastic and capillary phenomena opens new perspectives in designing materials with exotic properties such as negative compressibility [6].

Fig. 1 Hydrophobically gated memristive nanopore (HyMN) [3]. a) schematic representation of electrowetting in a model hydrophobic nanopore. b) experimental realization of hysteresis cycle in engineered FraC nanopore.

References

1. Roth, R., & Kroll, K. M. (2006). Capillary evaporation in pores. Journal of Physics: Condensed Matter, 18(28), 6517.
2. Eroshenko, V., Regis, R. C., Soulard, M., & Patarin, J. (2001). Energetics: a new field of applications for hydrophobic zeolites. Journal of the American Chemical Society, 123(33), 8129-8130.
3. Cambiaso, S., Rasera, F., Tinti, A., Bochicchio, D., Grosu, Y., Rossi, G., & Giacomello, A. (2024). Grafting heterogeneities rule water intrusion and extrusion in nanopores. Communication Materials,
4. Paulo, G., Sun, K., Di Muccio, G., Gubbiotti, A., Morozzo della Rocca, B., Geng, J., … & Giacomello, A. (2023). Hydrophobically gated memristive nanopores for neuromorphic applications. Nature Communications, 14(1), 8390.
5. Aryal, P., Sansom, M. S., & Tucker, S. J. (2015). Hydrophobic gating in ion channels. Journal of molecular biology, 427(1), 121-130.
6. Caprini, D., Battista, F., Zajdel, P., Di Muccio, G., Guardiani, C., Trump, B., … & Giacomello, A. (2024). Bubbles enable volumetric negative compressibility in metastable elastocapillary systems. Nature Communications,

Bio: Alberto Giacomello is Associate Professor of Fluid Dynamics at Sapienza University and principal investigator of the ERC-StG project HyGate. His research is in theoretical and computational fluid mechanics of interfaces at the micro- and nano-scale. He is keen on understanding the origin of metastability in problems of engineering and multidisciplinary interest, including ion channel gating, superhydrophobicity, contact angle hysteresis, nanobubbles, and cavitation inception. AG obtained a MS in Mechanical Engineering from Sapienza University of Rome and the Polytechnic Institute of New York University in 2010. AG holds a PhD in Theoretical an Applied Mechanics from Sapienza. In 2014 AG moved to Germany to work as postdoc at the Max Planck Institute for Intelligent Systems of Stuttgart. AG is the recipient of the AIMETA Junior Prize in Fluid Mechanics and a Junior Fellow of the Sapienza School for Advanced Studies (SSAS).