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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.