Molecular design and fundamental understanding of Janus Mixed Matrix Membranes with precisely controlled morphology and transport properties

University Of Oklahoma Norman Campus, Norman OK

Investigators

Abstract

Separating carbon dioxide from a mixture of gases is an important aspect of reducing emissions and generating quality methane or hydrogen fuel. However, current membrane materials suffer a trade-off between selectivity and permeability, meaning separations that achieve purer products require more time. In this project, the investigators aim to improve both the quality and speed of the separation using Janus nanoparticles embedded in a polymer membrane. Janus nanoparticles have two faces, in reference to the character in Roman mythology. In this case, one face is covered with silver and the other contains tails of a polymer called Jeffamine. Both the silver and the Jeffamine components facilitate CO2 transport through the membrane. This project has the potential to advance the US economy and quality of life, as is will contribute to reducing the nation's dependency of traditional separation technologies, lightening energy bills, and limiting harmful emissions in the atmosphere. The investigators also plan to mentor a diverse group of student researchers and present their results through learning modules for high school students and public events. This proposal aims to discover fundamental structure-property correlations regarding how silver and polyether (Jeffamine) components of a Janus nanoparticle contribute, individually and synergistically, to transport properties when incorporated into a polymer membrane. The investigators hypothesize that the anisotropic character of the Janus particle will lead to improved membrane transport properties such as high permeability, high selectivity, and fewer defects. To test this hypothesis, the investigators will synthesize two series of membranes, one containing an increasing amount of Janus nanoparticles with a fixed polyether tail length, and second with a fixed amount of Janus nanoparticles exhibiting different lengths polyether tail lengths. The chemical structure, particle size and silver content of the nanoparticles will be measured before adding them to the polymer membrane. Membrane characterization will include, thermal, free volume, gravimetric and structural characterizations such as the dispersion of nanoparticles, chain-packing, and domain spacing. The outcome of the proposed activities will be fundamental understanding of how Janus nanoparticle characteristics, such as the number of ether groups in the polyether tail, can be used to improve both CO2 selectivity and permeability. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.