Water-Polyamide Chemical Interplay in Desalination Membranes explored by Ambient Pressure X-ray Photoelectron Spectroscopy

Published

June 24, 2020

Author(s)

Sabrina Gericke, William D. Mulhearn, Dana E. Goodacre, Joseph Raso, Daniel J. Miller, Lauryn Carver, Slavomir Nemsak, Osman Karslioglu, Lena Trotochaud, Hendrik Bluhm, Christopher Stafford, Christin Buechner

Abstract

Reverse osmosis using aromatic polyamide membranes is currently the most important technology for seawater desalination. The performance of reverse osmosis membranes is highly dependent on the interplay of their surface chemical groups with water and water contaminants. We study ultrathin polyamide films that chemically resemble reverse osmosis membranes, using ambient pressure X-ray photoelectron spectroscopy. This technique can identify the functional groups at the membrane-water interface and allows monitoring small shifts in the electron binding energy that indicate interaction with water. We observe deprotonation of free acid groups and formation of a ‘water complex' with nitrogen groups in the polymer upon exposure of the membrane to water vapor. The chemical changes are reversed when water is removed from the membrane. While the correlation between functional groups and water uptake is an established one, this experiment serves to understand the nature of their chemical interaction, opening possibilities for tailoring future materials to specific requirements.

Citation

Physical Chemistry Chemical Physics

Volume

22

Issue

27

Pub Type

Journals

Download Paper

https://doi.org/10.1039/d0cp01842b

Local Download

Keywords

ambient pressure, x-ray photoelectron spectroscopy, polyamide, membranes, desalination, humidity

Citation

Gericke, S. , Mulhearn, W. , Goodacre, D. , Raso, J. , Miller, D. , Carver, L. , Nemsak, S. , Karslioglu, O. , Trotochaud, L. , Bluhm, H. , Stafford, C. and Buechner, C. (2020), Water-Polyamide Chemical Interplay in Desalination Membranes explored by Ambient Pressure X-ray Photoelectron Spectroscopy, Physical Chemistry Chemical Physics, [online], https://doi.org/10.1039/d0cp01842b, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=929804 (Accessed December 12, 2024)