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In this work we demonstrate that cell pressure controls the morphology and stability of electroplated sodium metal deposits on carbon black nucleation layers in ether-based electrolytes. At pressures below 500 kPa we observe the presence of three-dimensional Na nuclei accompanied by low Coulombic efficiencies (CEs less than 98%). Conversely, at pressures between 500 and 1272 kPa we observe smooth, planar Na deposits, high CEs up to 99.9%, and stable electrochemical cycling. Through a series of tests conducted at elevated current densities and with or without rest stages, our findings elucidate the balance of important competing time scales for creep and morphology evolution under pressure and the rate of charge transfer that determines Na morphology and stability. This highlights how chemo-mechanical effects at pressure ranges relevant for battery packaging in coin and pouch cells are key factors in the design and operation of Na metal batteries. 

The diffusion of colloids, nanoparticles, and small molecules near the gas–liquid interface presents interesting multiphase transport phenomena and unique opportunities for understanding interactions near the surface and interface. Stratification happens when different species preside over the interfaces in the final dried coating structure. Understanding the principles of stratification can lead to emerging technologies for materials’ fabrication and has the potential to unlock innovative industrial solutions, such as smart coatings and drug formulations for controlled release. However, stratification can be perplexing and unpredictable. It may involve a complicated interplay between particles and interfaces. The surface chemistry and solution conditions are critical in determining the race of particles near the interface. Current theory and simulation cannot fully explain the observations in some experiments, especially the newly developed stratification of nano-surfactants. Here, we summarize the efforts in the experimental work, theory, and simulation of stratification, with an emphasis on bridging the knowledge gap between our understanding of surface adsorption and bulk diffusion. We will also propose new mechanisms of stratification based on recent observations of nano-surfactant stratification. More importantly, the discussions here will lay the groundwork for future studies beyond stratification and nano-surfactants. The results will lead to the fundamental understanding of nanoparticle interactions and transport near interfaces, which can profoundly impact many other research fields, including nanocomposites, self-assembly, colloidal stability, and nanomedicine. 

Background: Project management and other professional skill training is often lacking in graduate student education, typically as a result of limited resources, lack of faculty buy-in, and narrow focus on thesis research. To address this need and with support from NSF, we are developing the Graduates for Advancing Professional Skills (GAPS) program at Iowa State University. To aid the initial development of this program, we conducted a literature review to understand the current context of the development and implementation of professional skills in higher education curricula, with specific interest in STEM fields. Purpose: The purpose of our study was to identify best practices related to implementing professional development skills into an academic curriculum. The goal was to utilize this information in the development, planning, implementation, and assessment of our GAPS program. Design: We engaged in a systematic literature review. We focused on the curricular and pedagogical approaches to implementing these skills, results of the initiatives, and methodologies used to assess their effectiveness. Results: Our literature review uncovered the “messiness” of teaching and learning of skills such as project management. There is often not one approach or definition of project management – it may change based on scope of project and context. Successful implementation requires adaptability, mentorship, problem solving, creativity, and communication. Additionally, project management has been referred to as a “threshold concept” and requires a certain level of intuition that cannot necessarily be gained through traditional classroom education. Conclusions: There appears to be an agreement on the importance of implementing project management skills at the postsecondary level. Our work illustrates the difficulty associated with undertaking this endeavor and provides guidance on approaches that can make these initiatives more beneficial. Although this literature was conducted to aid in the planning for our specific project, the synthesis of the extant works can inform other faculty and industry leaders who are interested in teaching and applying project management techniques in their courses or companies.