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Graphene oxide (GO) membranes, known for their high dielectric constant and low dielectric loss, have emerged as promising separators for advanced energy storage and transfer devices. While previous research has focused on the aqueous stability enhancement by high-valence metal cations, their effect on modifying the dielectric properties of GO membranes remains understudied. This study investigates the impact of transition metal cation modification on the aqueous stability and dielectric properties of graphene oxide (GO) membranes. Multivalent transition metal chlorides (FeCl3, FeCl2, CuCl2, and CuCl) were introduced during the self-assembly process to create modified GO membranes. The membranes were characterized using various techniques, including zeta potential measurements, contact angle measurements, FTIR spectroscopy, and XRD spectroscopy. The aqueous stability of the modified membranes was evaluated, and their dielectric performance was assessed using capacitance measurements across a frequency range of 0.1 Hz to 105 Hz. The results demonstrate that the choice of transition metal cation and its oxidation state significantly influence the morphology, aqueous stability, and dielectric properties of the GO membranes. Notably, Fe3+ and Cu2+ modifications enhanced aqueous stability, while Fe2+ and Cu+ modifications improved dielectric performance. This study provides insights into tailoring the properties of GO membranes for various applications, including energy storage and transfer devices. 

Traditionally, materials science labs were independent weekly labs, aiming to reinforce the lecture content and provide students with hands-on experience. The Union College Mechanical Engineering department has been redeveloping the curriculum to make it more inclusive and meet the college-wide general education goal, one of which is connecting disciplinary content with complex global challenges. This paper presents the approach of consolidating the 3–4 independent materials science labs into one project that addresses real world challenges. In the materials-based project-based lab（PB-Lab), students work in groups and identify the provided materials (morphological, structural, property, process) to create solutions for a scenario in an ongoing global crisis with set timeframes and constraints. The curriculum design of PB-Lab engages students with active learning and authentic learning; they see how what they are learning in materials sciences can be applied as working engineers. Students experience the interdependent and integrated nature of the materials development process in the lab and generate their own concepts about addressing global challenges. In summary, PB-Lab engages students in identifying problems, developing potential solutions through materials characterization and analysis in the lab, and delivering effective communication in the form of lab reports or presentations. 

Abstract While hexagonal boron nitride (hBN) has been widely used as a buffer or encapsulation layer for emerging electronic devices, interest in utilizing it for large‐area chemical barrier coating has somewhat faded. A chemical vapor deposition process is reported here for the conformal growth of hBN on large surfaces of various alloys and steels, regardless of their complex shapes. In contrast to the previously reported very limited protection by hBN against corrosion and oxidation, protection of steels against 10% HCl and oxidation resistance at 850 °C in air is demonstrated. Furthermore, an order of magnitude reduction in the friction coefficient of the hBN coated steels is shown. The growth mechanism is revealed in experiments on thin metal films, where the tunable growth of single‐crystal hBN with a selected number of layers is demonstrated. The key distinction of the process is the use of N₂gas, which gets activated exclusively on the catalyst's surface and eliminates adverse gas‐phase reactions. This rate‐limiting step allowed independent control of activated nitrogen along with boron coming from a solid source (like elemental boron). Using abundant and benign precursors, this approach can be readily adopted for large‐scale hBN synthesis in applications where cost, production volume, and process safety are essential.