Nanovoid-Enhanced Thin-Film Composite Reverse Osmosis Membranes Using ZIF-67 Nanoparticles as a Sacrificial Template

Qipeng Zhao; Die Ling Zhao; Mui Hoon Nai; Shing Bor Chen; Tai-Shung Chung

doi:10.1021/acsami.1c07673

Nanovoid-Enhanced Thin-Film Composite Reverse Osmosis Membranes Using ZIF-67 Nanoparticles as a Sacrificial Template

ACS Appl Mater Interfaces. 2021 Jul 21;13(28):33024-33033. doi: 10.1021/acsami.1c07673. Epub 2021 Jul 8.

Authors

Qipeng Zhao¹, Die Ling Zhao¹, Mui Hoon Nai², Shing Bor Chen¹, Tai-Shung Chung^{1

3}

Affiliations

¹ Department of Chemical and Biomolecular Engineering, National University of Singapore 4 Engineering Drive 4, Singapore 117585, Singapore.
² Department of Biomedical Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117583, Singapore.
³ Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, Taipei 10607, Taiwan.

PMID: 34235913
DOI: 10.1021/acsami.1c07673

Abstract

In this work, nanovoid-enhanced thin-film composite (TFC) membranes have been successfully fabricated using ZIF-67 nanoparticles as the sacrificial template. By incorporating different amounts of ZIF-67 during interfacial polymerization, the resultant TFC membranes can have different degrees of nanovoids after self-degradation of ZIF-67 in water, consequently influencing their physiochemical properties and separation performance. Nanovoid structures endow the membranes with additional passages for water molecules. Thus, all the newly developed TFC membranes exhibit better separation performance for brackish water reverse osmosis (BWRO) desalination than the pristine TFC membrane. The membrane made from 0.1 wt % ZIF-67 shows a water permeance of 2.94 LMH bar^-1 and a salt rejection of 99.28% when being tested under BWRO at 20 bar. This water permeance is 53% higher than that of the pristine TFC membrane with the salt rejection well maintained.

Keywords: ZIF-67; brackish water desalination; nanovoids; reverse osmosis; thin-film composite membrane.