Graphene scientists at the University of Manchester have developed a new “nano Petri dish” that uses two-dimensional (2D) materials to create a new way to observe particle motion.
Published in the journal Nature, a team led by researchers based at the National Graphene Institute (NGI) used stacks of 2D materials including graphene to trap liquids to better understand the presence of a liquid changes the nature of a solid.
For the first time, the team photographed an atom “suspended” in a liquid. The results could have far-reaching implications for the future development of green technologies such as hydrogen production. When a solid surface comes into contact with a liquid, the two substances change configuration to react with close proximity.
Such atomic-scale interactions at the solid-liquid interfaces govern the operation of batteries and fuel cells for clean power generation, and also determine the efficiency of clean water production and maintenance of biological processes. Study on a large scale. One of the lead researchers, Professor Sarah Haigh, commented: “Given the broad scientific and industrial implications of such behavior, it is surprising how much we still have to learn about the underlying principles. Version of the behavior of atoms on liquid-contact surfaces, for reasons of lack of information, techniques cannot provide experimental data for the solid-liquid interface.
Transmission electron microscopy (TEM) is one of the few techniques for viewing and analyzing individual atoms. However, TEM equipment requires a high vacuum environment and the structure of the material changes in the vacuum. First author Dr Nick Clark explains: “In our work we have shown that misinformation is provided when the behavior of atoms is studied in a vacuum rather than using our liquid cells.” NGI Professor Roman Gorbachev has pioneered 2D material stacking for electronics, but here his team has used similar techniques to create a “dual graphene liquid cell”.
The 2D molybdenum sulfide layer is completely suspended in the liquid and enclosed around the graphene windows. This new design allows them to deliver precisely controlled layers of liquid, enabling unprecedented video capture of a “suspended” atom surrounded by liquid. By analyzing how the atoms move in the video and comparing them with the theoretical views of colleagues at the University of Cambridge, researchers have discovered the influence of liquids on the behavior of atoms.
Liquids were found to speed up the motion of the atoms and also change their preferred resting positions relative to the underlying solid. The team has been working on a promising material for green hydrogen production, but the experimental technology they developed could be used for a variety of applications. Dr Nick Clark said: “This is an important step and just the beginning – we are looking to use this technique to support the development of materials for the sustainable chemical processing needed to achieve zero global ambition.”
