{"id":{"repo_id":"gatech","oai_identifier":"oai:repository.gatech.edu:1853/78648"},"canonical_url":"https://search.dev.ndltd.org/etd/gatech/oai:repository.gatech.edu:1853/78648","repository":{"repo_id":"gatech","name":"Georgia Tech","base_url":"https://repository.gatech.edu/server/oai/request"},"display":{"title":"Advanced characterization of transport and microstructural properties in membrane materials","abstract":"Membranes are employed in a variety of sustainable water treatment and energy conversion technologies. Advancing membrane materials for new separations includes unraveling the complex structure-property relationships that govern water and salt transport in conjunction with scaling processing methods. Material properties can be tuned by increasing salinity, adjusting humidity, or introducing filler particles to achieve desired transport metrics. These modifications impact water and salt diffusion as well as microstructural characteristics in the membrane materials, yet the detailed relationships between membrane performance, processing conditions, and transport properties remain to be fully characterized. Although extensive membrane research has been conducted, a need exists to better understand how compositional changes impact transport in membrane materials as well as resulting membrane properties. Understanding the structure- property-processing relationships of membrane materials is crucial for optimizing performance in practical applications. Here, I examine three classes of membrane materials used in water treatment and energy conversion applications: polyamide reverse osmosis membranes, Nafion cation (proton) exchange ionomers, and graphene oxide-based nanofiltration membranes. Advanced characterization techniques quantify water diffusion coefficients and relaxation times in polymer membranes under varying environmental conditions. Additionally, aggregation behaviors and interlayer binding interactions between graphene oxide sheets and intercalant molecules are examined. Diffusion measurements reveal distinct transport mechanisms of water and salt in charged and uncharged polymer membrane materials. Aggregation behavior observed in graphene oxide (GO) dispersions and salt rejection measurements with GO membranes bridges the gap between fundamental material properties and the membrane performance.","abstract_html":"Membranes are employed in a variety of sustainable water treatment and energy conversion technologies. Advancing membrane materials for new separations includes unraveling the complex structure-property relationships that govern water and salt transport in conjunction with scaling processing methods. Material properties can be tuned by increasing salinity, adjusting humidity, or introducing filler particles to achieve desired transport metrics. These modifications impact water and salt diffusion as well as microstructural characteristics in the membrane materials, yet the detailed relationships between membrane performance, processing conditions, and transport properties remain to be fully characterized. Although extensive membrane research has been conducted, a need exists to better understand how compositional changes impact transport in membrane materials as well as resulting membrane properties. Understanding the structure- property-processing relationships of membrane materials is crucial for optimizing performance in practical applications. Here, I examine three classes of membrane materials used in water treatment and energy conversion applications: polyamide reverse osmosis membranes, Nafion cation (proton) exchange ionomers, and graphene oxide-based nanofiltration membranes. Advanced characterization techniques quantify water diffusion coefficients and relaxation times in polymer membranes under varying environmental conditions. Additionally, aggregation behaviors and interlayer binding interactions between graphene oxide sheets and intercalant molecules are examined. Diffusion measurements reveal distinct transport mechanisms of water and salt in charged and uncharged polymer membrane materials. Aggregation behavior observed in graphene oxide (GO) dispersions and salt rejection measurements with GO membranes bridges the gap between fundamental material properties and the membrane performance.","abstract_has_math":false,"creators":["Garell, Madeline"],"institution":"Georgia Institute of Technology","degree_name":null,"degree_level":"Doctoral","degree_discipline":null,"degree_department":"Mechanical Engineering","school":null,"contributors":[],"advisors":["Hatzell, Marta C."],"committee_chairs":[],"committee_members":["Menon, Akanksha","Lee, Seung Woo","Hesketh, Peter","Nair, Sankar"],"year":2025,"date_issued":"2025-05-15","date_published":"2025-05-15","updated_at":"2026-07-27T19:48:57Z","subjects":["Membranes","nuclear magnetic resonance","polyamide","Nafion","graphene oxide"],"languages":["en_US"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/1853/78648","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Hatzell, Marta C."]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["Menon, Akanksha","Lee, Seung Woo","Hesketh, Peter","Nair, Sankar"]},{"key":"dc:contributor.department","label":"Department","values":["Mechanical Engineering"]},{"key":"dc:creator","label":"Author","values":["Garell, Madeline"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2025-08-15T12:39:51Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2025-08-15T12:39:51Z"]},{"key":"dc:date.issued","label":"Date","values":["2025-05-15"]},{"key":"dc:publisher","label":"Institution","values":["Georgia Institute of Technology"]},{"key":"dc:type","label":"Dc Type","values":["Text"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Doctoral"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Membranes","nuclear magnetic resonance","polyamide","Nafion","graphene oxide"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en_US"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://hdl.handle.net/1853/78648"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Membranes are employed in a variety of sustainable water treatment and energy conversion technologies. Advancing membrane materials for new separations includes unraveling the complex structure-property relationships that govern water and salt transport in conjunction with scaling processing methods. Material properties can be tuned by increasing salinity, adjusting humidity, or introducing filler particles to achieve desired transport metrics. These modifications impact water and salt diffusion as well as microstructural characteristics in the membrane materials, yet the detailed relationships between membrane performance, processing conditions, and transport properties remain to be fully characterized. Although extensive membrane research has been conducted, a need exists to better understand how compositional changes impact transport in membrane materials as well as resulting membrane properties. Understanding the structure- property-processing relationships of membrane materials is crucial for optimizing performance in practical applications. Here, I examine three classes of membrane materials used in water treatment and energy conversion applications: polyamide reverse osmosis membranes, Nafion cation (proton) exchange ionomers, and graphene oxide-based nanofiltration membranes. Advanced characterization techniques quantify water diffusion coefficients and relaxation times in polymer membranes under varying environmental conditions. Additionally, aggregation behaviors and interlayer binding interactions between graphene oxide sheets and intercalant molecules are examined. Diffusion measurements reveal distinct transport mechanisms of water and salt in charged and uncharged polymer membrane materials. Aggregation behavior observed in graphene oxide (GO) dispersions and salt rejection measurements with GO membranes bridges the gap between fundamental material properties and the membrane performance."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Ph.D."]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Advanced characterization of transport and microstructural properties in membrane materials"]}]}],"canonical_facts":{"dc:contributor.advisor":["Hatzell, Marta C."],"dc:contributor.committeemember":["Menon, Akanksha","Lee, Seung Woo","Hesketh, Peter","Nair, Sankar"],"dc:contributor.department":["Mechanical Engineering"],"dc:creator":["Garell, Madeline"],"dc:date.accessioned":["2025-08-15T12:39:51Z"],"dc:date.available":["2025-08-15T12:39:51Z"],"dc:date.issued":["2025-05-15"],"dc:description.abstract":["Membranes are employed in a variety of sustainable water treatment and energy conversion technologies. Advancing membrane materials for new separations includes unraveling the complex structure-property relationships that govern water and salt transport in conjunction with scaling processing methods. Material properties can be tuned by increasing salinity, adjusting humidity, or introducing filler particles to achieve desired transport metrics. These modifications impact water and salt diffusion as well as microstructural characteristics in the membrane materials, yet the detailed relationships between membrane performance, processing conditions, and transport properties remain to be fully characterized. Although extensive membrane research has been conducted, a need exists to better understand how compositional changes impact transport in membrane materials as well as resulting membrane properties. Understanding the structure- property-processing relationships of membrane materials is crucial for optimizing performance in practical applications. Here, I examine three classes of membrane materials used in water treatment and energy conversion applications: polyamide reverse osmosis membranes, Nafion cation (proton) exchange ionomers, and graphene oxide-based nanofiltration membranes. Advanced characterization techniques quantify water diffusion coefficients and relaxation times in polymer membranes under varying environmental conditions. Additionally, aggregation behaviors and interlayer binding interactions between graphene oxide sheets and intercalant molecules are examined. Diffusion measurements reveal distinct transport mechanisms of water and salt in charged and uncharged polymer membrane materials. Aggregation behavior observed in graphene oxide (GO) dispersions and salt rejection measurements with GO membranes bridges the gap between fundamental material properties and the membrane performance."],"dc:description.degree":["Ph.D."],"dc:format.mimetype":["application/pdf"],"dc:identifier.uri":["https://hdl.handle.net/1853/78648"],"dc:language.iso":["en_US"],"dc:publisher":["Georgia Institute of Technology"],"dc:subject":["Membranes","nuclear magnetic resonance","polyamide","Nafion","graphene oxide"],"dc:title":["Advanced characterization of transport and microstructural properties in membrane materials"],"dc:type":["Text"],"thesis:degree_level":["Doctoral"]},"updated_at":"2026-07-27T19:48:57Z"}