LaMer Award – 97th ACS Colloid and Surface Science Symposium

Haichao Wu obtained his BS in Chemical Engineering from Shandong University (2014), and his MS in Chemical Engineering from Carnegie Mellon University (2015), working under the supervision of Prof. Stephen Garoff, Prof. Robert Tilton, and Prof. Todd Przybycien. He obtained his PhD in Chemical Engineering from University of Colorado Boulder (2021) under the supervision of Prof. Daniel K. Schwartz, where he investigated transport phenomena (e.g., diffusion, advection, and self-propulsion) in porous media using single-particle tracking methods. Currently, Haichao is a postdoctoral fellow in Prof. Joanna Aizenberg’s group, developing active motion-driven materials.

From the granular and fractured subsurface environment to highly engineered polymer membranes, porous materials are ubiquitous in nature and industrial applications. In particular, porous media are used extensively in processes including water treatment, pharmaceutical sterilization, and heterogeneous catalysis. Unfortunately, there are currently no universal models capable of predicting mass transport based on a description of the porous material because real porous materials are complex and because many coupled dynamic mechanisms (e.g., adsorption, steric effects, hydrodynamic effects, electrostatic interactions, etc.) give rise to the observed macroscopic transport phenomena.

While classical techniques, like nuclear magnetic resonance and dynamic light scattering, provide useful information about mass transport in porous media at the ensemble level, they provide limited insight into the microscopic mechanisms that give rise to complex phenomena such as anomalous diffusion, hindered pore-space accessibility, and unexpected retention under flow, among many others. To address this issue, we have developed refractive index matching imaging systems, combined with single-particle tracking methods, allowing the direct visualization of single-particle motion within a variety of porous materials.

In this talk, I will present my work in advancing the understanding of nanoparticle transport in porous media using single-particle tracking methods in both fundamental and applied scenarios. In particular, (1) understanding fundamental particle transport processes in porous media, including pore accessibility and cavity escape, which limit transport in porous media, and (2) facilitating applications in industrial processes, e.g., by understanding the mechanisms of particle fouling and remobilization during membrane filtration processes.

The Division of Colloid and Surface Chemistry presents the Victor K. LaMer Award for Graduate Research in Colloid and Surface Chemistry annually at the Colloid and Surface Science Symposium. Named for Victor K. LaMer, the award is for an outstanding Ph.D. thesis accepted by a US or Canadian university during the three year period prior to the award year. The presentation of the 53rd LaMer Award will occur during the Wednesday morning plenary.

Candidates for the 53rd LaMer Award must have had their Ph.D. thesis accepted between September 1, 2019 and August 31, 2022. Details about the Award and the nomination process are available here.

The LaMer Award selection committee is pleased to announce the 2023 award recipient:

Nanoparticle tracking to probe transport in porous media