Breaking the ice
Climate change has underscored the enormously consequential role of natural ice formations in the environment. It also makes the nature of ice itself an especially important area of study, and examinations of the clean surfaces of ice in vacuums and of ice in water vapor have yielded significant insight into the physical properties of ice.
To better understand ice in natural conditions, the interface between ice and water must be thoroughly analyzed. And while atomic force microscopy (AFM) has emerged as a powerful tool that excels at analyzing many properties of ice, the fluctuation of the interface of ice and water presents a challenge for the scanning technology.
To examine the properties of ice in liquid environments, Yanagisawa et al. demonstrated the applicability of AFM using organic solvents instead of water. The team built an experimental system to observe and analyze the interface of ice and three different alcohols.
“For the first time, we successfully observed a very small structure (0.1 nm in height) on the ice surface in liquid using AFM,” said author Hiroshi Onishi. “Additionally, the obtained images revealed that ice has different surface structures depending on the type of alcohol.”
The researchers could measure the force curves in the liquids to analyze the Young’s modulus of the ice, a property that determines how easily it can stretch and deform.
“Ice is a very familiar material in our lives, yet its fundamental properties still hold many mysteries. In particular, the true nature of ice in liquid is not well understood,” said author Taketoshi Minato. “Our results open new possibilities for clarifying its true nature.”
Source: “The interface between ice and alcohols analyzed by atomic force microscopy,” by Ryo Yanagisawa, Tadashi Ueda, Kei-ichi Nakamoto, Zhengxi Lu, Hiroshi Onishi, and Taketoshi Minato, Journal of Chemical Physics (2024). The article can be accessed at https://doi.org/10.1063/5.0211501 .
This paper is part of the Water: Molecular Origins of its Anomalies Collection, learn more here .