Publication Highlights – 2024

This set of studies focuses on manufacturing, particularly the printing and evaporative deposition of nanoparticles. In this field, particle size and zeta potential are crucial for ensuring the colloidal stability of nanoparticles. At the nanoscale, size influences their function—whether in plasmonic resonance properties, electronic band structure, or even magnetic behavior. To maintain particle stability in solution, adjusting the surface charge is important. A common approach is to modify the storage solution to optimize the zeta potential, either positively or negatively, creating a net repulsive force between particles, which reduces flocculation and sedimentation.

The first study highlights a freestanding monolayer of CrOCl created via chemical exfoliation. CrOCl has gained attention in the field of 2D materials due to its complex magnetic properties in bulk form. Researchers at Princeton University chemically exfoliated CrOCl using organolithium reagent lithiation, achieving stable nanosheets with a zeta potential around -17 mV. This work is particularly intriguing because of the unique characteristics of the material and the changes observed between its bulk and exfoliated forms.

Villalpando, Graciela, et al. "Freestanding monolayer CrOCl through chemical exfoliation." Nanoscale Horizons 9.10 (2024): 1766-1773. https://doi.org/10.1039/D4NH00137K

The second study, from the Max Planck Institute, focuses on creating intricate micro- and nanoscaffolds for high-uniformity 3D microstructures with substantial mass loading. They fine-tuned the zeta potential, lowering it to around -5 mV, which minimized electrostatic repulsion so particles remained stable in solution but formed coatings as the solution dried. By refining a dip-coating method with capillary trapping, they were able to work with various materials—polymers, metals, and metal oxides—and produce complex 3D structures.

Lyu, Xianglong, et al. "Capillary trapping of various nanomaterials on additively manufactured scaffolds for 3D micro-/nanofabrication." Nature Communications 15.1 (2024): 6693. https://doi.org/10.1038/s41467-024-51086-2

The third paper, a large collaborative effort among six universities and the U.S. Air Force Research Laboratory (including the University of Utah, Sungkyunkwan University, Georgia Tech, the University at Buffalo, and Brown University), combines mathematical modeling, simulations, and custom-engineered devices. The team created a model and experimental setup to test how factors such as particle size, charge, flow rate, and temperature affect particle migration during evaporative deposition. One interesting aspect is the team’s hypothesis that atmospheric CO₂ absorption changes the local ionic strength at the evaporative interface, impacting particle distribution. Such extensive collaboration is rare, and this work holds significant potential for advancing large-scale manufacturing processes.

Ghosh, Samannoy, et al. "Diffusiophoresis-enhanced particle deposition for additive manufacturing." MRS communications 13.6 (2023): 1053-1062. https://doi.org/10.1557/s43579-023-00432-4

Altogether, these studies illustrate the importance of zeta potential—and how Wyatt instruments contribute—to stabilizing inorganic nanoparticles in solution for effective additive manufacturing.