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Title: Unique selectivity trends of highly permeable PAP[5] water channel membranes
Artificial water channels are a practical alternative to biological water channels for achieving exceptional water permeability and selectivity in a stable and scalable architecture. However, channel-based membrane fabrication faces critical barriers such as: (1) increasing pore density to achieve measurable gains in permeability while maintaining selectivity, and (2) scale-up to practical membrane sizes for applications. Recently, we proposed a technique to prepare channel-based membranes using peptide-appended pillar[5]arene (PAP[5]) artificial water channels, addressing the above challenges. These multi-layered PAP[5] membranes (ML-PAP[5]) showed significantly improved water permeability compared to commercial membranes with similar molecular weight cut-offs. However, due to the distinctive pore structure of water channels and the layer-by-layer architecture of the membrane, the separation behavior is unique and was still not fully understood. In this paper, two unique selectivity trends of ML-PAP[5] membranes are discussed from the perspectives of channel geometry, ion exclusion, and linear molecule transport.  more » « less
Award ID(s):
1709522
PAR ID:
10101195
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Faraday Discussions
Volume:
209
ISSN:
1359-6640
Page Range / eLocation ID:
193 to 204
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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