Peter Kusalik

While much of the science of Chemistry occurs in the liquid state, or at liquid or solid interfaces, a detailed understanding of these systems at the molecular level has yet to be achieved. Physical phenomena such as crystallization and self-assembly are ubiquitous in nature, yet the microscopic mechanisms involved remain obscure and relatively inaccessible to experimental probes. The principal goal of Dr. Kusalik’s research program is to probe microscopic behavior of liquids, solids and their interfaces, to demonstrate how local molecular structure and dynamics relate to various properties and processes of condensed phase systems, and to apply this understanding in creative and transformative ways to real-world problems. We provide insights into many aspects of crucial phenomena within and on the surfaces of systems such as water and ice, thereby impacting many areas within and beyond Chemistry. While our primary objective is to provide new knowledge and insights within specific areas, the broad range of problems being addressed implies excellent opportunities for innovation and for significant impact and long-term benefit.

Dr. Kusalik research program incorporates several interconnected and complementary areas that build on our established leadership. These include the structure and dynamics in liquid systems and at liquid/solid and liquid/gas interfaces, and their relationships to ordering and self-assembly processes and to the stability and mobility of bulk nanobubbles (NBs). It focuses on 3 different research areas: 
1) nucleation and crystal growth from aqueous systems; 
2) self-assembly of metal-organic framework materials (MOFs), and 
3) stability and mobility of aqueous NBs. 
In (1) and (2) we will address issues such as characterization of microscopic mechanisms and identification of the key factors and driving forces. (1) and (3) involve water and aqueous systems in which we have had long standing interest and have considerable experience and expertise. Molecular simulation and multiscale modeling will be common themes across this work, where we will continue to pioneer advanced analysis and visualization tools, including machine learning, allowing for significant advances and groundbreaking results to be achieved. This research program both builds on areas of strength and explores highly original and innovative directions, where many application areas are possible, e.g. improved atmospheric models, better synthetic methods for MOFs, greatly enhanced water treatments, and control of crystal fiber growth.

Nanobubbles (NBs), also known as ultrafine bubbles, are gas-filled bubbles in water with typical diameters in the ~100 nm range. The study of NBs in bulk aqueous solution has only recently come under focused scientific investigation, with a number of review articles appearing recently. While several features of NBs are consistently reported, most notably being stable in water for long periods of time (e.g. weeks or months), there remains considerable uncertainty and debate regarding the nature and properties of bulk NBs (e.g. the origin of their unexpected stability). Their very small size results in NBs having very large surface area to volume ratios and negligible buoyancy. Importantly, NBs can dramatically enhance the total amount of gas present in water while apparently not impacting the solute concentration in aqueous solution. The tremendous potential of NBs across various applications has been highlighted in several recent reviews. Viewed as solutions that benefit from increased amounts of gas with significantly enhanced gas transfer rates, NBs have potential for major impacts across a wide range of fields and technologies, from environmental remediation, water treatment to food production.

In this research project, we focus on 3 key areas, (1) the generation, (2) the characterization, and (3) the control of bulk NBs. We will employ a very recent novel approach, that efficiently catalyzes NB generation utilizing electric fields,to overcome the major limitations that have restricted the potential impacts of NBs to this point (i.e., high energy costs, modest concentrations and lack of scalability). In Area 1, we are looking to determine factors critical for the rapid and efficient generation of bulk NBs in high concentrations (e.g. >0.1% by volume) with the goal of identifying a scalable generator design suitable for operations across a wide range of applications. Area 2 will focus on the characterization of NBs using a wide range of experimental probes, many of which have not been used previously in this context. Our objectives are to determine key physical and rheological properties that provide important insights and advance our understanding of NBs, and to identify unique features in their behavior. In Area 3, we examine the response of NBs to electric fields and to ultrasound, thereby further enhancing the potential for development of revolutionary technologies applicable to a wide range of industries and applications.