Tannic acid modified MoS2 nanosheet membranes with superior water flux and ion/dye rejection

Wenjihao Hu; Xinwei Cui; Li Xiang; Lu Gong; Ling Zhang; Mingwen Gao; Wenda Wang; Jiawen Zhang; Fenglin Liu; Bin Yan; Hongbo Zeng

doi:10.1016/j.jcis.2019.10.068

Tannic acid modified MoS₂ nanosheet membranes with superior water flux and ion/dye rejection

J Colloid Interface Sci. 2020 Feb 15:560:177-185. doi: 10.1016/j.jcis.2019.10.068. Epub 2019 Oct 18.

Authors

Wenjihao Hu¹, Xinwei Cui², Li Xiang¹, Lu Gong¹, Ling Zhang¹, Mingwen Gao¹, Wenda Wang¹, Jiawen Zhang¹, Fenglin Liu¹, Bin Yan³, Hongbo Zeng⁴

Affiliations

¹ Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada.
² Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada; College of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, China. Electronic address: langocui@hotmail.com.
³ College of Light Industry, Textile & Food Engineering, Sichuan University, Chengdu 610065, China. Electronic address: yanbinscu@126.com.
⁴ Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada. Electronic address: hongbo.zeng@ualberta.ca.

PMID: 31670015
DOI: 10.1016/j.jcis.2019.10.068

Abstract

Energy-efficient membranes are urgently needed for water desalination and separation due to ever-increasing demand for fresh water. However, it is extremely challenging to increase membrane water flux and simultaneously achieve high rejection rates of cations or organic dyes. Herein, we report a tannic acid (TA) assisted exfoliation method to fabricate TA-modified MoS₂ (TAMoS₂) nanosheets with high production yield (90 ± 5%). The TAMoS₂ nanosheets membranes show excellent non-swelling stability in water. It is found that a hybrid membrane with 1 wt% of TAMoS₂ in MoS₂ nanosheets demonstrates overall better performance than pure MoS₂ and TAMoS₂ membrane. Such a hybrid membrane with a thickness of 5 µm shows fast water flux at around 32 L m^-2 h^-1 (LMH) and >97% rejection of various cations under static diffusion mode. Under vacuum-driven filtration condition, the as-prepared hybrid membrane demonstrates ultrafast water flux of 15,000 ± 100 L/(m² h bar) and 99.87 ± 0.1% rejection of multiple model organic dyes. To the best of our knowledge, the above performances are superior to those of all MoS₂-based membranes reported previously in terms of water flux and ion/dye rejection. This work represents a leap forward towards the practical applications of 2D TAMoS₂ membranes in various engineering and environmental areas.

Keywords: 2D materials; Molybdenum disulfide membranes; Organic dye separation; Rejection rate of cations; Water flux.