Supporting Information

Selective Synthesis of WO3 and W18O49 Nanostructures: Ligand-free pH-Dependent Morphology Controlled Self-assembly of Hierarchical Architecture from 1D Nanostructure and Sunlight-driven Photocatalytic Degradation

Y. M. Shirke and S. Porel-Mukherjee

Fig. S1. UV-VIS-NIR profile comparison between products W-1.5, W-1.76 & W-2.05 and W-2.05 showing an absorption tail in the NIR region that may arise from the presence of oxygen vacancy.

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W-2.05

W-1.76W-1.5

Abso

rban

ce

Wavelength (nm)

Electronic Supplementary Material (ESI) for CrystEngComm.This journal is © The Royal Society of Chemistry 2017

Fig. S2. FTIR spectrum of the as-prepared W-1.5 and W-2.05.

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W-1.5

W-2.05

Tran

smitt

ance

Wavenumber/cm-1

W-O

O-W-O

Fig. S3. N2 adsorption/desorption isotherms for (a) W-0.95, (b) W-1.5, (c) W-1.76, (d) W-2.05 and (e) W-2.35.

0.0 0.2 0.4 0.6 0.8 1.0

0

20

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60

80

100Vo

lum

e @ST

P(cc

/g)

Relative pressure (p/p0)

(a)

0.0 0.2 0.4 0.6 0.8 1.0

0

40

80

120

160

Volu

me @

STP(

cc/g

)

Relative pressure (p/p0)

(b)

0.0 0.2 0.4 0.6 0.8 1.0

0

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80

120

160

Volu

me @

STP(

cc/g

)

Relative pressure(p/p0)

(c)

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0

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Volu

me @

STP(

cc/g

)

Relative pressure (p/p0)

(d)

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0

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160

200

Volu

me @

STP(

cc/g

)

Relative pressure (p/p0)

(e)

Fig. S4. SEM images of the products (a) W-0.95, (b) W-1.5, (c) W-1.76, (d) W-2.05 and (e) W-2.35. Scale bar = 3 m

(a) (b) (c)

(d) (e)

Fig. S5. TEM images and the corresponding ED pattern (inset) of the products (a) W-0.95, (b) W-1.5, (c) W-1.76, (d) W-2.05 and (e) W-2.35; with reference WO3 (hkl = white colour) and W18O49 (hkl = blue colour).

(b)

001002

003

220221

312

(a)221 001

002003

(e)

010

(d)

010020

030

(c)

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201020

221

010101

100

Fig. S6. Full range XPS spectra of (a) W-1.5 and (b) W-2.05

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Inte

nsity

(a.u

.)

Binding Energy (eV)

W4f

O1s

(a)

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Inte

nsity

(a.u

.)

Binding Energy (eV)

W4f

O1s

(b)

Fig. S7. Raman spectra obtained at laser power 20 mW for the products (a) W-0.95, (b) W-1.5, (c) W-1.76, (d) W-2.05 and (e) W-2.35.

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an In

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ity

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an In

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(e)

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Ram

an In

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ity

Wavenumber/cm-1

(d)

200 nm

Fig. S8. (a) SEM and (b) TEM image of product W-2.35 disassembled by aqueous ultrasonication under a long treatment time.

(a) (b)

Fig. S9. The change observed in UV-Vis absorbance spectra in the presence of (a) W-1.5 and (b) W-2.05 under sunlight irradiation for different times.

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0.5

1.0

Wavelength (nm)

0 min 1 min 2 min 5 min 7 min 10 min 15 min 30 min

(b)

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0.5

1.0

1.5Ab

sorb

ance

Wavelength(nm)

0 min 1 min 2 min 5 min 7 min 10 min 15 min 30 min 45 min 60 min

(a)