-S1-

Supporting Information (SI)

New Core-Substituted Naphtalenediimides anchored on BiVO4 for

Visible Light-Driven Water Splitting

Simelys Hernández,a,b,* Carminna Ottone,c Stefano Proto,d Kristhine Tolod,a

Miriam Díaz de los Bernardos,d Albert Solé-Daura,e Jorge J. Carbó,e Cyril

Godard,e Sergio Castillón,f Nunzio Russo,a Guido Saracco,b Carmen Claver,d,e*

a CREST group, Department of Applied Science and Technology (DISAT), Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin, Italy.b Center for Sustainable Future Technologies (CSFT@Polito), Italian Institute of Technology, Corso Trento 21, 10129, Turin, Italy.c School of Biochemical Engineering, Pontificia Universidad Catolica de Valparaiso. Av. Brasil 2085, Valparaiso, Chile.d Centre Tecnològic de la Química a Catalunya (CTQC), CarrerMarcel·lí Domingo s/n, Edifici N5, 43007, Tarragona, Spain.e Departament of Química Física i Inorgànica, Universitat Rovira i Virgili, CarrerMarcel·lí Domingo s/n, 43007, Tarragona, Spain. f Department of Química Analítica i Química Orgànica, Universitat Rovira i Virgili, CarrerMarcel·lí Domingo s/n, 43007, Tarragona, Spain.

*corresponding authors: E-mail: simelys.hernandez@polito.it, carmen.claver@ctqc.org

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

-S2-

Table of Contents:

Fig. S1: NMR and FT-IR spectra of N,N′-dipyridyl 1,4,5,8-naphthalenetetracarboxylic acid dianhydride (dye 1)

Fig. S2: NMR and FT-IR spectra of N,N’-Di-(2,6-diisopropylphenyl)-2,6-dibromonaphthalene-1,4,5,8-tetracarboxylic acid bisimide (Br,Br-NDI)

Fig. S3: NMR and FT-IR spectra of N,N’-Di-(2,6-diisopropylphenyl)-2-aminobenzoic acid-6-bromonaphthalene-1,4,5,8-tetracarboxylic acid bisimide (dye 2)

Fig. S4: NMR and FT-IR spectra of N, N’-Di-(2,6-diisopropylphenyl)-2-aminobenzoic acid-6-dimethylamine-naphthalene-1,4,5,8-tetracarboxylic acid bisimide (dye 3)

Fig. S5: NMR and FT-IR spectra of N,N’-Di-(2,6-diisopropylphenyl)-2-aminobenzoic acid-6-bromonaphthalene-1,4,5,8-tetracarboxylic acid bisimide (dye 4)

Fig. S6: Photographs of dyes solutions in acetonitrile (a). UV-Visible spectra (b) and molecular structures (c) and of dyes 1-4.

Fig. S7: Characterization of dye 1-BiVO4.

Fig. S8: TGA Analysis of dyes 2, 3 and 4 on BiVO4.

Table S1: Energy Levels of dyes.

Fig. S9: Cyclic voltammetry curves for the dyes 1 to 4 for the experimental calculation of energy levels.

-S3-

Fig. S1: N,N′-dipyridyl 1,4,5,8-naphthalenetetracarboxylic acid dianhydride (dye 1):

(a) 1H NMR (400 MHz, TFA-d, 298K): δ 9.03 (d, J= 4.0 Hz, 4H), 8.94 (s, 4H), 8.26 (d, J= 4.0 Hz, 4H).

0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.510.511.512.5f1 (ppm)

-500

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

5500

4.24

8.00

8.27

8.28

8.94

9.02

9.03

11.5

0

(b) 13C NMR (100.5 MHz, TFA-d,298K): δ154.5, 145.5, 135.3, 131.7, 130.0, 1 129.1, 127.6.

0102030405060708090100110120130140150160170180190f1 (ppm)

-50

0

50

100

150

200

250

300

350

400

450

500

112.

1011

4.39

114.

9211

5.42

117.

2111

7.74

120.

5612

6.96

128.

4712

9.36

131.

1013

4.70

144.

87

154.

48

163.

2916

3.73

164.

1616

4.60

N N

O

O O

O

NN

1

-S4-

(c) FT-IR: 3036.37, 1710.44, 1659.93, 1578.45, 1488.29, 1445.39, 1384.64, 1350.89, 1248.68,

1197.58, 1149.37, 1126.71, 1088.62, 985.92, 863.95, 830.20, 769.46, 752.58, 716.91,

689.53, 620.96, 608.43 cm–1.High resolution Mass Spectroscopy analysis, MS (HR-ESI)

yield sm/z: observed 421.0942 [M+H+] and calculated 421.0937.

N N

O

O O

O

NN

1

-S5-

Fig. S2: N,N’-Di-(2,6-diisopropylphenyl)-2,6-dibromonaphthalene-1,4,5,8-tetracarboxylic acid bisimide(Br,Br-NDI):

(a) 1H NMR (400 MHz, CDCl3, 298K): 9.12 (s, 2H), 7.53 (d, J =8.0 Hz, 2H), 7.34 (d, J = 8.0 Hz, 4H), 2.65 (sept, J= 4.0 Hz, 4H), 1.17 (d, J = 4.0 Hz, 24H).

0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.510.0f1 (ppm)

0

500

1000

1500

2000

2500

3000

3500

4000

4500

25.8

9

4.62

4.18

2.60

2.00

1.17

1.18

1.26

2.65

5.29

7.26

7.35

7.37

7.52

9.12

(b) 13C NMR (101.5 MHz, CDCl3, 298K): 161.2, 161.2, 145.6, 139.9,130.5, 130.1, 129.4, 129.0, 125.6, 124.9, 124.7, 29.7, 24.3.

0102030405060708090100110120130140150160170180190f1 (ppm)

-5

0

5

10

15

20

25

30

35

40

4524.2

9

29.7

430

.04

77.0

477

.36

77.6

8

124.

6812

4.89

125.

9612

8.94

129.

3613

0.11

130.

48

139.

90

145.

67

161.

2016

1.23

N

N

OO

O O

Br

Br

i-Pri-Pr

i-Pri-Pr

6

-S6-

(c) FT-IR: 2958.75, 1720.19, 1677.77, 1560.61, 1413.57, 1353.78, 1309.43, 1225.55,

1056.80, 896.70, 827.70, 802.24, 786.33, 718.84, 625.79, 606.50 cm-1. MS (HR-ESI) yields m/z:

observed 745.1063 [M+H+] and calculated 745.5240.

N

N

OO

O O

Br

Br

i-Pri-Pr

i-Pri-Pr

6

-S7-

Fig. S3: N,N’-Di-(2,6-diisopropylphenyl)-2-aminobenzoic acid-6-bromonaphthalene-1,4,5,8-tetracarboxylic acid bisimide (dye 2):(a) 1H NMR (400 MHz, CDCl3, 298K): 12.07 (s, 1H), 9.00 (s, 1H), 8.72 (s, 1H), 8.69 (d, J = 4.0 Hz, 2H),7.51 (t, J = 8.0 Hz, 1H), 7.43 (t, J = 8.0 Hz, 1H), 7.37 (d, J = 8.0 Hz, 2H), 7.31 (d, J = 8.0 Hz, 2H), 7.26 (d, J = 4.0 Hz, 2H), 2.67 (sept, J = 6.8 Hz, 2H), 2.61 (sept, J = 6.8 Hz, 2H), 1.37- 1.02 (m, 24H).

(-1012345678910111213

f1 (ppm)

-50

0

50

100

150

200

250

300

350

400

450

500

550

600

650

700

25.9

0

3.77

9.13

3.00

0.95

0.96

0.88

1.02

1.16

1.37

2.60

2.68

5.28

7.22

7.31

7.36

7.42

7.52

7.72

8.69

8.72

9.00

12.0

7

b) 13C NMR (101.5 MHz, CD2Cl2): 166.8, 162.1, 161.6, 151.2, 149.2, 145.7, 142.8, 139.6, 132.6, 130.3, 129.4, 128.3, 127.2, 126.7, 126.3, 125.8, 124.7, 124.5, 124.1, 123.2, 122.8, 117.4, 102.9, 42.9, 42.1, 34.1, 32.3, 31.4, 24.3, 23.1, 14.45.

0102030405060708090100110120130140150160170180190f1 (ppm)

-20

0

20

40

60

80

100

120

140

160

180

200

220

240

260

280

300

320

340

360

14.4

823

.05

24.3

124

.35

24.4

229

.67

29.7

230

.02

30.0

532

.28

42.1

142

.94

102.

99

114.

4111

7.42

122.

8512

4.55

124.

7312

6.30

127.

0912

8.26

129.

46

139.

6314

2.78

145.

6614

5.76

149.

2615

1.87

161.

6416

1.96

162.

0516

6.83

N

N

OO

O OHN

Br

i-Pri-Pr

i-Pri-Pr

OH

O

-S8-

(c) FT-IR: 2961.16, 2925.00, 1721.16, 1682.11, 1644.98, 3, 2923.56, 2851.24, 1644.02, 1582.79,

1570.74, 1514.33, 1438.64, 1315.70, 1261.22, 1224.58, 1173.95, 938.20, 870.74, 836.96, 804.17,

788.74, 765.60, 722.69, 698.89, 626.27, 618.55, 609.87 cm-1.MS (HR-ESI)yields m/z: observed

800.2149 [M+H]+ and calculated 801.2237.

N

N

OO

O OHN

Br

i-Pri-Pr

i-Pri-Pr

OH

O

-S9-

Fig. S4: N, N’-Di-(2,6-diisopropylphenyl)-2-aminobenzoic acid-6-dimethylamine-naphthalene-1,4,5,8-tetracarboxylic acid bisimide (dye 3):

(a) 1H NMR (400 MHz, CDCl3, 298K): 11.48 (s, 1H), 8.87 (s, 2H), 8.60 (s, 1H), 8.12 (d, J = 8.0 Hz, 2H 1H), 7.53 (t, J = 8.0 Hz, 1H), 7.47 (t, J = 8.0 Hz, 1H), 7.40-7.32 (m,8H), 3.20 (s, 6H), 2.74 (m, 4H), 1.34- 1.15 (m, 24H).

-0.50.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.510.511.512.5f1 (ppm)

-50

0

50

100

150

200

250

300

350

400

450

500

550

600

36.8

7

3.47

4.18

6.80

1.69

1.08

0.91

1.00

1.15

1.17

1.19

1.21

1.26

1.29

1.34

2.72

2.74

3.20

7.32

7.34

7.38

7.40

7.47

7.53

8.10

8.12

8.60

8.87

11.4

3

(b) 13C NMR (101.5 MHz, CDCl3): 167.1, 163.4, 163.3, 161.9, 152.2, 145.8, 132.5, 131.3, 130.6, 130.2, 129.9, 127.4, 124.7, 124.6, 123.4, 121.3, 120.6, 114.2, 107.3, 44.5, 30.1, 24.5, 24.4, 24.3, 24.1.

-100102030405060708090100110120130140150160170180f1 (ppm)

-1000

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000

11000

12000

13000

14000

1500024.1

224

.34

24.4

524

.54

30.0

5

44.4

6

107.

32

114.

4112

1.32

123.

4412

4.37

124.

6012

4.95

127.

3912

9.90

130.

2213

0.59

131.

2913

2.45

145.

8214

5.86

152.

22

161.

8816

3.28

163.

3716

7.10

N

N

OO

O OHN

Me2N

i-Pri-Pr

i-Pri-Pr

OH

O

-S10-

(c) FT-IR: 2922.59, 1693.19, 1644.02, 1584.24, 1513.36, 1468.05, 1220.24, 1173.03, 966.64,

906.38, 873.59, 845.63, 804.65, 788.74, 716.91 cm-1. MS (HR-ESI)yields m/z: observed

763.3509 [M+H]+ and calculated 764.3574.

N

N

OO

O OHN

Me2N

i-Pri-Pr

i-Pri-Pr

OH

O

-S11-

Fig.S5: N,N’-Di-(2,6-diisopropylphenyl)-2-aminobenzoic acid-6-bromonaphthalene-1,4,5,8-tetracarboxylic acid bisimide (dye 4):

(a) 1H NMR (400 MHz, CDCl3-MeOH, 298K): 11.30 (s, 2H), 8.79 (s, 2H), 8.04 (d, J = 8.0 Hz, 4H), 7.44 (t, J = 8.0 Hz, 2H), 7.34 (d, J = 8.0 Hz, 4H), 7.29 (d, J = 8.0 Hz, 4H), 3.29 (s, 2H), 2.66-2.59 (m, 4H), 1.18-1.08 (m, 24H).

-0.50.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.510.010.511.011.512.012.5f1 (ppm)

24.5

0

4.08

2.12

4.00

3.96

2.11

4.01

2.05

2.00

-0.0

0

1.08

1.10

1.12

1.18

2.59

2.61

2.62

2.64

2.66

3.29

7.29

7.30

7.33

7.35

7.42

7.44

7.46

8.03

8.05

8.79

11.3

0

(b) 13C NMR (101.5 MHz, CD2Cl2-MeOH): 165.6, 165.6, 161.7, 145.5, 144.5, 130.7, 129.0, 128.9, 125.3, 123.3, 122.6, 120.9, 120.7, 103.2, 32.8, 30.9, 28.7, 28.6, 28.4, 28.3, 23.0, 22.9, 21.7.

-100102030405060708090100110120130140150160170180f1 (ppm)

-0.0

0

13.0

722

.97

22.9

928

.27

28.3

928

.68

28.7

1

47.5

847

.79

48.0

148

.22

48.4

3

103.

25

120.

7712

0.86

122.

6312

3.31

125.

3412

8.97

129.

0313

0.75

144.

5314

5.52

161.

6816

5.57

165.

62

N

N

OO

O OHN

NH

i-Pri-Pr

i-Pri-Pr

O

OH

O

HO

-S12-

(c) FT-IR: 2927.08, 2861.70, 1682.01, 1648.86, 1600.05, 1477.57, 1411.26, 1280.49, 1231.69,

1190.24, 1100.00, 878.98, 797.02, 731.63, 699.40 cm-1. MS (HR-ESI) yieldsm/z: observed

857.3550 [M+H]+and calculated 858.35.

N

N

OO

O OHN

NH

i-Pri-Pr

i-Pri-Pr

O

OH

O

HO

-S13-

Fig. S6: Photographs of dyes solutions in acetonitrile (a).UV-Visible spectra (b) and molecular structures (c) and of dyes 1-4.

dye 1 dye 2 dye 3 dye 4

200 300 400 500 600 700 800 900

dye 1 dye 2 dye 3 dye 4

Abs

(a.u

.)

Wavelenght (nm)

600

555 660580520

893

390

370337

350

280312

323

237210

216-220

350 370

(a)

(b)

(c)

-S14-

Fig. S7: Characterization of dye 1-BiVO4: (a) FTIR spectrum and (b) TGA under air atmosphere and (c) XRD spectrum. Legend: bare Dye 1 (gray), bare BiVO4 (orange) and dye1 substituted BiVO4 (blue).

(a)

N

N

O O

OO

BiVO4

dye 1

Toluene / DMF

N

N

120 °C

N

N

OO

O O

N

N

500 1000 1500 2000 2500 3000 3500

wavenumber (cm-1)

200 400 600 800

0

20

40

60

80

100

% w

eigh

t

temperature (ºC)

10 20 30 40 50 60 70degree)

(b)

(c)

-S15-

Fig. S8: TGA Analysis of dyes2, 3 and 4 on BiVO4.Legend: dye 2 (red), dye 3 (pink), dye 4 (blue), bare BiVO4 (black) and dye-substituted BiVO4 (green).

200 400 600 800

0

20

40

60

80

100

% w

eigh

t

temperature (ºC)

N

N

OO

O O

BiVO4

Me2N

HN

O

O

i-Pri-Pr

i-Pr i-PrN

N

OO

O O

BiVO4

Br

HN

O

O

i-Pri-Pr

i-Pr i-Pr

BiVO4N

N

OO

O O

NH

HN

N

i-Pri-Pr

i-Pr i-Pr

N

dye 2

BiVO4

dye 2 + BiVO4 dye 3 + BiVO4

dye 4

BiVO4BiVO4

dye 4 + BiVO4

dye 3

200 400 600 800

0

20

40

60

80

100

% w

eigh

t

temperature (ºC)200 400 600 800

0

20

40

60

80

100

% w

eigh

t

temperature (ºC)

-S16-

Table S1: Energy Levels of dyes. Comparison of computed (BP86 and PBE functionals) and experimentally determined (Exp.) HOMO and LUMO energies, and band gap (Eg). Energies, mean values between experimental and BP86 results, and average errors respect to experimental values (av. error) in eV.

HOMO [eV] LUMO [eV] Eg [eV]

Exp. BP86 Mean value PBE Exp. BP86 Mean

value PBE Exp. BP86 Mean value

Dye 1 -6.35 -6.20 -6.28 -6.04 -3.66 -4.13 -3.9 -4.04 2.69 2.07 2.38

Dye 2 -5.53 -5.49 -5.51 -5.39 -3.95 -4.01 -3.98 -3.90 1.58 1.48 1.53

Dye 3 -5.16 -4.94 -5.05 -4.84 -3.65 -3.69 -3.67 -3.58 1.51 1.26 1.39

Dye 4 -5.4 -5.09 -5.25 -4.98 -3.82 -3.88 -3.85 -3.78 1.57 1.21 1.40

av. error 0.18 0.30 0.16 0.13 0.34 0.17

Fig. S9: Cyclic voltammetry curves for the dyes 1 to 4 for the experimental calculation of energy levels. Experimental conditions: acetonitrile electrolyte, scan rate of 100 mV/s under N2 flow. The values of onset-potential of oxidation (Eox) and reduction (Ered) are given in the legend.