Towards a fundamental understanding of ice crystallization and melting through bulk water nanoengineering

• Applicant: Dr. Shuai Li
• Subject Area: Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry ; Mechanical Process Engineering
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 535007237

The primary focus of this research project is to delve into the intricate mechanisms underlying the crystallization and melting processes of ice crystals at the microscale/nanoscale in aqueous solutions and suspensions. The aim is to achieve a deeper understanding of these fundamental processes and develop more efficient strategies for controlling ice nucleation, growth, and recrystallization in bulk supercooled water. Throughout this project, we will explore the influence of various factors, including salt ions, nanomaterials (such as nanowires and 2D materials like graphene oxide), and ice-adsorbing polymers, on these phenomena. Outlined below are three specific objectives that will guide our investigations: Objective 1: Enhancing our comprehension of the ice nucleation process in bulk supercooled water. This objective entails a meticulous examination of the ice nucleation temperature and the impact of additives. To this end, we will use salts, 1D and 2D nanomaterials, and polymers with diverse properties such as sizes, charges, or molecular weights as our primary experimental tools. Through the utilization of advanced optical microscopy techniques, we will closely observe the freezing process, allowing us to develop physical models that accurately describe the observed results. Objective 2: Unraveling the intricacies of ice growth (recalescence and solidification) in bulk water at the microscale. This objective revolves around a comprehensive study of the kinetics governing ice crystal growth and the influence of additives. By examining the growth rates of ice crystals under varying additive conditions, we will interpret the outcomes based on the principles of thermodynamics. This investigation will provide valuable insights into the underlying dynamics of ice growth, facilitating a holistic understanding of these processes. Objective 3: Investigating the ice recrystallization process at the microscale. This objective encompasses a detailed analysis of the kinetics involved in recrystallization, alongside an evaluation of the effectiveness of additives in inhibiting this process. Additionally, we will try to unravel the underlying mechanisms driving ice recrystallization by employing a combination of experimental investigations and theoretical modeling. By pursuing these three specific objectives with rigor and employing state-of-the-art experimental techniques, we anticipate making significant contributions to our understanding of ice crystallization and melting processes. Moreover, the insights gained from this research will have broad-ranging implications across numerous scientific disciplines, spanning materials science, climate science, and cryobiology, ultimately driving advancements and innovations in these fields.

• DFG Programme: WBP Fellowship
• International Connection: USA
• Host: Thomas Schutzius, Ph.D.