Texas A&M University researchers, led by Dr. Hamidreza Samouei, are increasing their understanding of what makes nanobubbles—bubbles with diameters smaller than a single strand of hair—so stable, as well as the elements that influence their stability. Their findings appeared in a recent issue of The Journal of Physical Chemistry.
Image Credit: Dr. Hamidreza Samouei
Bubbles are one method of keeping gases in solution, which is necessary for many chemical reactions. Nanobubbles are more stable than larger bubbles, which means they can stay in a solution for longer periods of time without popping. Their enhanced stability enables higher gas availability in solution, which gives chemical processes more time to take place.
When we inject gas at the industrial scale, we do not want to waste that gas. We want to maximize its use for chemical reactions. That is the main purpose, to keep the gas in solution for a very, very long time, ideally infinite time; to keep the gas in solution without bursting.
Dr. Hamidreza Samouei, Research Assistant Professor, Texas A&M University
Researchers have found that the electric charges of nanobubbles and the interactions between the bubbles’ charges and the solvent play a major role in their stability. The stability of nanobubbles is also impacted by any solution additives.
Nanobubbles have a wide range of practical applications, such as hydroponics, wastewater treatment, and disinfection, due to their capacity to retain gas in solution. In hydroponic farming, plants produced with nanobubbles grow larger than those grown without them. By increasing the amount of oxygen in the water, nanobubbles improve the conditions for crop growth.
Understanding nanobubble stability is only a small component of a larger research puzzle. Researchers have been infusing carbon dioxide into saltwater solutions to extract various minerals from them. The minerals obtained by this approach, known as brine mining, are employed in a wide range of applications, including lithium batteries and magnesium fertilizers.
Samouei added, “For this project, we wanted a way to increase carbon dioxide concentrations, so we used nanobubbles. Now that we have a better understanding of how to increase the lifetime of a nanobubble, they will be a key tool in brine mining practices.”
Dr. Mohammadjavad Karimi and Dr. Gholamabbas Parsafar have also contributed to this study.
Journal Reference:
Karimi, M., et al. (2024) Polarizing Perspectives: Ion- and Dipole-Induced Dipole Interactions Dictate Bulk Nanobubble Stability. The Journal of Physical Chemistry B. doi.org/10.1021/acs.jpcb.4c03973.
