Christopher Johnson

Current Research

I construct charge-selective membranes with self-assembling polymerizable surfactants to investigate the interplay of structure-property relationships and the motion of charged particles within ordered nanostructures. This work is focused on the physics of membranes designed for nanoparticle filtration, salt separations, organic separations, and fuel cells. I am a part of a Vagelos Institute of Energy Science and Technology (VIEST) seed group focusing on ordered nanofiltrations. Additionally, I was a recipient of a 2022-2023 VIEST Fellowship.

My specific research skills include structure identification through transmission and grazing-incidence small-angle x-ray scattering (SAXS/GISAXS) and materials property classification through dielectric spectroscopy (DS) and dynamic mechanical analysis (DMA), with proficiency in a gamut of methods (DSC, TGA, UV-Vis Spectroscopy, etc.). I also enjoy any technique that involves imaging. I have been involved in the startup of the soft matter autonomous experimentation section of the Osuji lab (Soft-AE) and can be approached with questions regarding our setup and software.

Publications and Presentations

• A pH- and Light-responsive Nanoporous Lyotropic Gyroid Polymer Network. P. Li, C. Johnson, S. S. Dyer, C. O. Osuji, D. L. Gin. Advanced Materials Interfaces (2022). doi:10.1002/admi.202201761
• Sulfonic-acid-based lyotropic bicontinuous cubic polymer network for molecular-size-selective heterogeneous catalysis. K. Culley, C. Johnson, D. L. Gin. Chemical Communications (2023)
• Effect of localized control of cross-link density on mechanical properties of bicontinuous cubic lyotropic networks via copolymerization with different singly-polymerizable monomers. Lauren N. Bodkin, Christopher W. Johnson, Keira E. Culley, Zachary A. Krajnak, Jeffrey R. Hage, Na Kyung Kim, Chinedum O. Osuji, Douglas L. Gin. Polymer (2023) https://doi.org/10.1016/j.polymer.2023.126615.
• Lyotropic Gyroid Mesophase Compositions, Polymer Compositions Comprising the Same, Methods of Preparation Thereof, and Methods of Using the Same. Gin, D.L., Li, P., Osuji, C., Imran, O., Johnson, C. and Dyer, S.S., University of Pennsylvania Penn and University of Colorado, 2023.  U.S. Patent Application 17/949,072.
• Presented a talk at ACS Fall Meeting 2023, entitled “Transport in Resilient Anion Exchange Membranes Derived from Crosslinked Lyotropic Mesophases”
• Presented a talk at ACS Fall Meeting 2024 entitled “Impact of direct hexagonal mesophase geometry and hydration on ion motion” in the Porous Polymers section.
• Presented posters at University of Pennsylvania Graduate Student Symposium in 2021 and 2022, as well as at the 2023 Center for Soft and Living Matter Symposium.
• The Effects of Morphology and Hydration on Anion Transport in Self-Assembled Nanoporous Membranes. Christopher W. Johnson, Lizhu Zhang, Keira E. Culley, Sol Mi Oh, Douglas L. Gin, Geoffrey M. Geise, Amish J. Patel, Karen I. Winey, and Chinedum O. Osuji. ACS Nano. 2025 19 (2), 2559-2569. doi:10.1021/acsnano.4c14234

Previous Research and Achievements

• Computational study of the self-assembly of generic brush-coil block copolymers with regards to changes in the architecture of the solvophilic brush block – supervised by Dr. Arthi Jayaraman (University of Delaware)

Cat

Properties of why I must run run run run now. Smaug the Cat, et al. Cat version of Science Advances, 2024.

A review of laps and why they are good to sit in. Poe the Cat, et al. Cat version of Nature, 2024