Underwater superoleophobic modified polysulfone

electrospun membrane with efficient antifouling for

ultrafast gravitational oil-water separation

M. Obaid1, Euntae Yang1, Dong-Hee Kang2, Myung-Han Yoon2, and In S. Kim1,*

1Global Desalination Research Center (GDRC), School of Earth Sciences and Environmental

Engineering, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu,

Gwangju 61005, South Korea.2School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), 123

Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Republic of Korea.

Corresponding author:

Tel: +82-62-715- 2436, Fax: +82-62-715-2434

E-mail: iskim@gist.ac.kr

Table S1: Conditions of modification process for the PSf electrospun membrane

Membrane code NaOH Conc. (M) Temp. (C) Time (h)

M1 0 25 1M2 0 50 1M3 0 75 1M4 0 100 1M5 0.1 25 1M6 0.1 50 1M7 0.1 75 1M8 0.1 100 1M9 0.5 25 1M10 0.5 50 1M11 0.5 75 1M12 0.5 100 1M13 1 25 1M14 1 50 1M15 1 75 1M16 1 100 1M17 0 25 3M18 0 50 3M19 0 75 3M20 0 100 3M21 0.1 25 3M22 0.1 50 3M23 0.1 75 3M24 0.1 100 3M25 0.5 25 3M26 0.5 50 3M27 0.5 75 3M28 0.5 100 3M29 1 25 3M30 1 50 3M31 1 75 3M32 1 100 3M33 0 25 5M34 0 50 5M35 0 75 5M36 0 100 5M37 0.1 25 5M38 0.1 50 5M39 0.1 75 5M40 0.1 100 5

M41 0.5 25 5M42 0.5 50 5M43 0.5 75 5M44 0.5 100 5M45 1 25 5M46 1 50 5M47 1 75 5M48 1 100 5M49 0 25 7M50 0 50 7M51 0 75 7M52 0 100 7M53 0.1 25 7M54 0.1 50 7M55 0.1 75 7M56 0.1 100 7M57 0.5 25 7M58 0.5 50 7M59 0.5 75 7M60 0.5 100 7M61 1 25 7M62 1 50 7M63 1 75 7M64 1 100 7

M8

M12 M16

M20 M24

M28 M32

M4

Fig.S1: FE SEM images for the PSf nanofiber membranes modified at 100oC for different

time and in various concertation of NaOH solutions.

Fig.S2: Water contact angle (WCA) of the pristine and modified membranes, where the x axis from 1 -64 represents the membrane code based on Table S1 and value 0 represent the

pristine PSf.

Fig.S3: Images of oil contact angle (OCA) under water of the modified membrane (M64).

Fig.S4: No water flux for the pristine PSf nanofiber membrane was obtained.

Table S2: Comparison of the performance of the modified membrane and various other membranes in literature in the oil/water separation under gravity.

Membrane Code Applied Preesure Oil Type

Water Flux

(LMH)

Separation Efficiency %

Refs.

PSF nanofiber membrane GravitySoybean oil/water mixture

>11,865 >99.99 This work

bio-based polycocolloid foam membrane Gravity Hexane/water

mixture >500 98 [1]

porous nitrocellulose (NC) membranes Gravity Gasoline/water

mixture~611

(calculated) >99 [2]

Elctrospun polyamide-PSf nanofiber membrane Gravity Oil/water

mixture 509 >99.9 [3]

PMMA-b-PNIPAAm nanofiber membrane

Gravity Hexane/water mixture 9400 >99.5 [4]

PHFBMA-b-PNIPAAm coated st.st. mesh Gravity Hexane/water

mixture 9000 >98 [5]

Mineral-coated membrane Gravity Dichloroethane/water mixture 90 >99.9 [6]

GO@CNF membrane Gravity Hexane/water mixture 960 >99 [7]

PVDF-g-PAA tree-like nanofiber membrane Gravity Hexane/water

mixture 9600 >99.58 [8]

APM-260 porous membrane Gravity

petroleum ether/ water

mixture1357 ~98 [9]

PAA-g-PVDF membranes Gravity

hexadecane/water

surfactant free emulsion

570 99.99 [10]

cellulose paper filter modified with NFC Gravity Hexane/water

emulsion 89.6 99 [11]

PVDF-TEA modified electrospun membrane Gravity Soybean/water

emulsion 2727 >99.9% [12]

Texture of the nylon membrane Gravity Hexadecane/

water 200 ≥ 99.9 [13]

emulsions

Polymer blend-coated Stainless steel mesh 400 Gravity Oil/water

emulsion 430 >99 [14]

A cellulose sponge Gravity Toluene/water emulsion 91 >99.94 [15]

Hygro-responsive membranes Gravity hexadecane-in-

water emulsion 90 >99 [16]

Reference

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