anti-biofouling organic-inorganic hybrid membrane for ... · anti-biofouling organic-inorganic...

Anti-biofouling organic-inorganic hybrid membrane for water

treatment

Ajay K. Singh1, Priyanka Singh

2, Sandhya Mishra

2, Vinod K. Shahi

*1

1 Electro-Membrane Processes Division,

2Salt and Marine Chemicals Division,

Central Salt & Marine Chemicals Research Institute, Council of Scientific & Industrial

Research (CSIR), G. B. Marg, Bhavnagar-364002 (Gujarat) INDIA Tel: +91-278-2569445; Fax: +91-278-2567562/2566970; E-mail: vkshahi@csmcri.org;

vinodshahi1@yahoo.com

S1. Biosafety precautions during the antibacterial and antifungal activity:

Bacteria/fungi are potentially hazardous and care should be taken while working with them.

Standard bio safety lab techniques were followed while handling bacteria/fungi and various

media. Gloves were used during all experimentation, and any accidental spills were

immediately sterilized using 70 % isopropanol/water followed by bleach. The work area was

also sterilized with 70 % isopropanol/water after completion of work. Unused media and

bacterial suspensions were first deactivated with commercial bleach for 1 h before being

disposed in bio safety bags. All material that had come in contact with bacteria (e.g., pipette

tips, tubes, agar plates, etc.) was also thrown in biosafety bags in tightly closed bins. Bio

safety bags were autoclaved for 2 h before final disposal.

S2. Water uptake measurements

The swelling ratio (Sw) for nanocomposite membranes was determined by water uptake

measurement using following equation (1):

)1(100)(

(%)

D

Dsw

m

mmS

Where mD is weight of dry membrane and ms is weight of wet membrane after wipe out

surface water by absorbing paper.

Electronic Supplementary Material (ESI) for Journal of Materials ChemistryThis journal is © The Royal Society of Chemistry 2011

S3. Dimensional changes

Dimensional changes of the membranes were investigated by square pieces of the membrane

was immersed in distilled water for 24 h, the surface was wiped and samples were dried at 70

C for 12 h. The thicknesses of membranes were measured by the Mitutoyo digimatic

micrometer. Length and width of membranes were measured by millimetre scale. Volume

fraction (Φ) of water was estimated by equation (2)

)2(zyx

zoyooxzyx

LLL

LLLLLL

Where, zyx LLL ,, may be the length/width/thickness of the swollen membrane and subscript

‘o’ represent the dimension in dry condition.

S4. Ion exchange capacity, surface charge concentration and void porosity

measurements

For determining ion exchange capacity (IEC), accurately weighted dry membrane was dipped

in 1.0 mol/L HCl for 24 h. Afterward the membrane was washed with distil water and then

immersed in 1.0 mol/L NaCl for 24 h. Exchanged H+ was titrated against 0.001 mol/L NaOH

solution using phenolphthalein indicator. The IEC was calculated according to the equation

(3).

)3().( 1

dry

solNa

W

VCmembranedrygmequivIEC

Where Wdry is the weight of the membrane sample under dry condition.

Electronic Supplementary Material (ESI) for Journal of Materials ChemistryThis journal is © The Royal Society of Chemistry 2011

With the help of IEC and water uptake capability determined the net surface charge density

(m) in the membrane was determined in unit of (moles of ionic sites)/ (unit volume of wet

membrane) by using the equation (4).

)4()(w

dm IEC

Where IEC is expressed in equivalent per gram of dry membrane, d the density of dry

membrane and τ denotes membrane voids porosity. Void porosity (volume of free water

within membrane per unit volume of wet membrane) can be obtained by using the equation

(5).

)5(1 w

w

Electronic Supplementary Material (ESI) for Journal of Materials ChemistryThis journal is © The Royal Society of Chemistry 2011

Fig. S1 1H NMR spectra (a) (COT) 5-(4-chlorophenyl)-1, 3, 4-oxadiazole-2-thiol in d6-

DMSO; (b) 2-(2-chloroethylthio)-5-(4-chlorophenyl)-1,3,4-oxadiazole in d6-DMSO; (c)

APDSMO in d6-DMSO.

Ajay

AJS -4

1 H nmr in Dmso, 200MHzYour comment here

(c)

(b)

ppm (t1)1.02.03.04.05.06.07.08.0

(a)

1 2 3

4 5 6 7

a

b c

d e

f g

h+i j+k+l

m n

Electronic Supplementary Material (ESI) for Journal of Materials ChemistryThis journal is © The Royal Society of Chemistry 2011

Fig. S2 13

C NMR spectra APDSMO in D2O.

(a+b)

(c+d)

(e)

(f+g)

(DMSO)

(h)

(i)

(j)

(n) (o)

(m) (l)

(p+q)

Electronic Supplementary Material (ESI) for Journal of Materials ChemistryThis journal is © The Royal Society of Chemistry 2011

Fig. S3 Synthesis route for hybrid membranes and TEM images of MO-6 membrane (a, b,

and c) at different magnifications.

(a) (b) (c)

2 nm 5 nm 10 nm

1 m

Electronic Supplementary Material (ESI) for Journal of Materials ChemistryThis journal is © The Royal Society of Chemistry 2011

Fig. S4 X-ray diffraction patterns for different hybrid membranes.

10 20 30 40 50 60

0

50

100

150

200

250

300

350

400

MO-6

MO-10

MO-3

Counts

/s

o2Theta

20 nm 20 nm

(A)

Hydrolysed

APDSMO

Electronic Supplementary Material (ESI) for Journal of Materials ChemistryThis journal is © The Royal Society of Chemistry 2011

Fig. S5 SEM image of (a-c) hydrolysed APSMO (low, medium and high resolution,

respectively); (d) MO-5 membrane.

(c) (e)

(j) (k)

(i)

(a)

(c)

(b)

(d)

Electronic Supplementary Material (ESI) for Journal of Materials ChemistryThis journal is © The Royal Society of Chemistry 2011

Fig. S6 TGA curve of different hybrid membranes.

100 200 300 400

20

40

60

80

100

%

weig

ht

loss

Temperature oC

MO-3

MO-5

MO-6

Electronic Supplementary Material (ESI) for Journal of Materials ChemistryThis journal is © The Royal Society of Chemistry 2011

Fig. S7 DSC spectra for MO-6 nanocomposite membranes.

100 200 300 400 500

-1.0

-0.5

0.0

0.5

1.0

R

efe

ren

ce te

mp

(oC

)

Sample temp (oC)

Electronic Supplementary Material (ESI) for Journal of Materials ChemistryThis journal is © The Royal Society of Chemistry 2011

Fig. S8 DMA thermogram for MO-6 membrane at 10 oC/ minute heating rate in N2

atmosphere.

50 100 150 200 250 300

0.0

0.1

0.2

0.3

0.4

Sto

rag

e m

od

ulu

s

Temperature oC

MO-6

Electronic Supplementary Material (ESI) for Journal of Materials ChemistryThis journal is © The Royal Society of Chemistry 2011

Fig. S9 Weight loss (%) for different hybrid membranes after treatment in 5% aqueous

NaOCl solution at 80 C for different time intervals.

0 10 20 30 40 50 60 70

0

1

2

3

4

5

% w

eig

ht

loss

Time (h)

MO-6

MO-5

MO-4

MO-3

Electronic Supplementary Material (ESI) for Journal of Materials ChemistryThis journal is © The Royal Society of Chemistry 2011

Fig. S10 Weight loss (%) for different hybrid membranes after treatment with different

concentrations of: (A) HCl and (B) H2SO4 for 30days.

1 2 3 4 5 6 7 8

0

2

4

6

8

10

12

14

16

18

20

22

24

%

we

igh

t lo

ss

Molar concentration of Sulphuric acid

MO-6

MO-5

MO-4

MO-3

1 2 3 4 5 6

0

2

4

6

8

10

12

14

16

18

% w

eig

ht

loss

Molar concentration of hydrochloric acid

MO-6

MO-5

MO-4

MO-3

(a)

(b)

Electronic Supplementary Material (ESI) for Journal of Materials ChemistryThis journal is © The Royal Society of Chemistry 2011

Fig. S11 Weight loss (%) for hybrid membranes in different organic solvents.

0.30 0.35 0.40 0.45 0.50 0.55 0.60

2

3

4

5

6

7

%

we

igh

t lo

ss

MO-x

NMP

DMF

DMSO

THF

Fig. S12 Ion exchange capacity (IEC) and water uptake values for different hybrid

membranes.

(d)

(g) (h)

25 30 35 40 45 50 55 60 65

1.0

1.1

1.2

1.3

IEC

% water

PVA/ APDSMPO

IEC

6

8

10

12

14

% W

ate

r up

take

APDSMO content (%)

Electronic Supplementary Material (ESI) for Journal of Materials ChemistryThis journal is © The Royal Society of Chemistry 2011

Fig. S13 24 h grown bacteria for membrane antifouling application (OD600=2.3299).

Electronic Supplementary Material (ESI) for Journal of Materials ChemistryThis journal is © The Royal Society of Chemistry 2011