1

Electronic Supplementary Information

Soranyel Gonzalez-Carrero, Guillermo Mínguez Espallargas, Raquel E. Galian* and Julia Pérez-Prieto*

Absorption and emission spectra of colloidal solutions of PODA1, POCA1, and PHXA1S2

Table S2: Emission lifetimes (and their corresponding contributions (A) to the total signal of the perovskites dispersed in toluene or as a spin-coated film.

S3

TGA Section: TGA heating curves of different perovskite and the precursor for their synthesis.

S5

1H-RMN Section: 1H-RMN (300 MHz) spectrum of PODA1 , PODA2 and their precursor in deuterated DMSO

S8

Quantification of dispersable perovskites A2PbBr4: PODA1, PODA2 and POCA2, Table S2-S4

S12

XPS Section: spectra of O1s, C1s, Pb4f, N1s and Br3d for PHX2, POCA2, and PODA2S15

TEM Section: HRTEM images of PHXA2, POCA2 and PODA2.S18

XRD Section: Observed and calculated profiles of the X-ray powder diffraction of PHX2, POCA2, PODA2 and PODA2np

S19

Photostability Studies: Photoluminescence of PHXA2, POCA2 and PODA2 dispersed in toluene as a function of the irradiation time (exc= 330 nm).

S21

Electronic Supplementary Material (ESI) for Journal of Materials Chemistry A.This journal is © The Royal Society of Chemistry 2015

2

0

0.5

1

1.5

2

300 400 500 600 700 800 900

Abs

orba

nce

Wavelength (nm)

a

0

0,5

1

1,5

2

2,5

3

300 350 400 450 500 550 600 650 700

Inte

nsity

(a.u

.)

Wavelength (nm)

b

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

300 400 500 600 700 800 900

Abs

orba

nce

Wavelength (nm)

c

0

1

2

3

4

5

6

300 350 400 450 500 550 600 650 700

Inte

nsity

(a.u

.)

Wavelength (nm)

d

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

300 400 500 600 700 800 900

Abs

orba

nce

Wavelength (nm)

e

0

2

4

6

8

10

300 350 400 450 500 550 600 650 700

Inte

nsity

(a.u

.)

Wavelength (nm)

f

Figure S1. Absorption and emission (λexc= 330 nm) spectra of colloidal solutions of PODA1 (1 mg/mL; a,b) POCA1 (0.6 mg/mL; c,d), and PHXA1 (0.2 mg/mL; e,f) and in toluene.

3

Table S1. Emission lifetimes (and their corresponding contributions (A) to the total signal of the perovskites dispersed in toluene or as a spin-coated film.

χ PLa

nmavb

ns ns

ns A1 A2

PODA1/air 1.19 397 9.345 3.154 30.155 96.975 3.025

PODA1/N2 1.28 397 8.840 3.120 31.560 97.580 2.420

Filmc 0.88 398 1.810 0.768 1.929 21.23 78.76

PODA2/air 1.40 397 4.192 2.773 27.89 99.41 0.592

PODA2/N2 1.50 397 3.833 2.650 27.33 99.51 0.486

Filmc 1.29 398 2.18 1.289 2.386 29.70 70.29

PHXA2/air 1.01 408 6.404 2.618 24.48 97.81 2.191

PHXA2/N2 1.21 408 6.413 2.413 22.15 97.31 2.695

POCA2/air 0.95 409 3.675 2.615 22.365 99.340 0.659

POCA2/N2 1.01 409 5.794 2.670 27.805 98.550 1.454

a Wavelength of the maximum emission (excitation at 340 nm); b av average lifetime; c Film prepared by spin-coating of toluene dispersion of the perovskite on quartz.

4

Quantification of dispersable A2PbBr4 perovskites

TGA and 1H-NMR analysis of the PHXA1, POCA1, PODA1, PHXA2, POCA2, and PODA2 perovskites

after purification and their supernatants (Ss) give valuable information on the composition of

these perovskites.

The first loss of weight in the perovskite samples was attributed to the loss of the organic capping of the material, i.e., ODE and ammonium salt (plus OLA in some samples) . The second step of the weight loss was ascribed to the loss of the ammonium bromide in the perovskite framework, while the third step is consistent with the loss of the perovskite lead bromide.

In the case of the supernatants, removal of the solvent followed by addition of ethyl ether

caused the precipitation of a solid (Ss). In addition, the ether solution was distilled, thus

recovering ODE with the ammonium salt (plus OLA in the case of the synthesis of PHXA1,

POCA1, and PODA1). For comparative purposes, the TGA of the individual precursors (namely

HXABr, OCABr, and ODABr ammmoniun salts) and the corresponding amines, as well as that

of ODE, OLA, and lead bromide, were also recorded and are included in TGA section.

Further data on the composition of PHXA, POCA and PODA samples were obtained from their 1H-

NMR spectra, which gave information on the molar ratio of the organic components (RMN

section). In combination with their TGA spectra, the PbBr2 weight percentage present in the

isolated mass was calculated. The 1H-NMR spectra of the supernatants were also analysed

(spectra not included); the data obtained from them combined with those of the corresponding

perovskite samples were consistent with the amount of material used in the preparation of the

perovskites.

The molar composition of PODA1, PODA2, PHXA2, and POCA2 , as well as the yield of isolated

perovskite (estimation based on the mmol of PbBr2 in the perovskite compared to the mmol

used in the reaction) are shown in Tables S2-S4.

5

Thermogravimetric Analysis Section

0

20

40

60

80

100

100 200 300 400 500 600 700 800

Wei

ght (

%)

Temperature (ºC)

a

-1.5

-1

-0.5

0

100 200 300 400 500 600 700 800

dm/d

t (m

g/m

in)

Temperature (ºC)

b

Figure S2. TGA heating curves of PHXA1 (-), POCA1 (-) and PODA1 (-) expressed as weight % as a function of applied temperature (a) and the corresponding 1st derivate (b).

0

20

40

60

80

100

100 200 300 400 500 600 700 800 900

Wei

ght (

%)

Temperature (ºC)

a

-1.2

-1

-0.8

-0.6

-0.4

-0.2

0

100 200 300 400 500 600 700 800

dm/d

t (m

g/m

in)

Temperature (ºC)

194 350º

541º

b

Figure S3. Comparison of TGA heating curves of PODA1 (-) and PODA2 (-) expressed as weight % as a function of applied temperature (a) and the correspondin1st derivate (b).

6

0

20

40

60

80

100

-5

-4

-3

-2

-1

0

0 100 200 300 400 500 600

Wei

ght (

%)

dm/dt (m

g/min)

Temperature (ºC)

a

0

20

40

60

80

100

-5

-4

-3

-2

-1

0

0 100 200 300 400 500 600

Wei

ght (

%)

dm/dt (m

g/min)

Temperature (ºC)

b

0

20

40

60

80

100

-5

-4

-3

-2

-1

0

0 100 200 300 400 500 600

Wei

ght (

%)

dm/dt (m

g/min)

Temperature (ºC)

c

0

20

40

60

80

100

-5

-4

-3

-2

-1

0

0 100 200 300 400 500 600

Wei

ght (

%)

dm/dt (m

g/min)

Temperature (ºC)

d

0

20

40

60

80

100

-5

-4

-3

-2

-1

0

0 100 200 300 400 500 600

Wei

ght (

%)

dm/dt (m

g/min)

Temperature (ºC)

e

0

20

40

60

80

100

-5

-4

-3

-2

-1

0

0 100 200 300 400 500 600

Wei

ght (

%)

dm/dt (m

g/min)

Temperature (ºC)

f

Figure S4. TGA heating curves of HXABr (a), hexyl amine HXA (b), OCABr (c) octylamine OCA (d), ODABr (e) and octadecylamine ODA (f) expressed as weight % as a function of applied temperature and the corresponding1st derivate.

7

0

20

40

60

80

100

-3

-2.5

-2

-1.5

-1

-0.5

0

0 200 400 600 800

Wei

ght (

%)

dm/dt (m

g/min)

Temperature (ºC)

a

0

20

40

60

80

100

-5

-4

-3

-2

-1

0

0 100 200 300 400 500 600

Wei

ght (

%)

dm/dt (m

g/min)

Temperature (ºC)

b

0

20

40

60

80

100

-5

-4

-3

-2

-1

0

0 100 200 300 400 500 600

Wei

ght (

%)

dm/dt (m

g/min)

Temperature (ºC)

c

Figure S5. TGA heating curve of lead bromide (a) ODE (b) and OLA (c) expressed as weight % as a function of applied temperature and the corresponding1st derivate.

0

20

40

60

80

100

-3

-2

-1

0

100 200 300 400 500 600 700

Wei

ght (

%)

dm/dt (m

g/min)

Temperature (ºC)

a

0

20

40

60

80

100

-3

-2

-1

0

100 200 300 400 500 600 700

Wei

ght (

%)

dm/dt (m

g/min)

Temperature (ºC)

b

Figure S6. TGA heating curves expressed as weight % as a function of applied temperature and the corresponding1st derivate of PODA1 Ss (a) and PODA2 Ss (b)

8

1H -RMN section

0.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.0ppm

3.08

30.7

0

2.12

0.11

0.05

2.00

0.08

2.96

0.83

0.85

0.87

1.06

1.23

1.46

1.49

1.51

1.54

1.99

2.01

2.27

2.73

2.76

2.78

7.65

0.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.0ppm

3.42

33.5

5

2.04

0.38

2.00

0.41

0.23

2.91

0.83

0.85

0.87

1.06

1.09

1.11

1.23

1.49

1.51

1.53

1.99

2.01

2.08

2.73

2.76

2.78

4.95

4.95

5.01

7.63

Figure S7. 1H-RMN (300 MHz) spectrum of PODA1 (a) and PODA2 (b) in deuterated DMSO.

a

b

9

Octylammonium bromide

1.01.52.02.53.03.54.04.55.05.56.06.57.07.58.0ppm

2.92

29.6

8

2.06

2.00

3.00

0.83

0.85

0.87

1.24

1.47

1.49

1.52

1.54

2.73

2.76

2.78

7.65

Figure S8. 1H NMR (300 MHz) spectrum of octylammonium bromide (ODABr) in deuterated DMSO.

1H NMR (300 MHz, d-DMSO) (300 MHz, DMSO) δ 7.65 (s, 3H), 2.76 (t, J = 7.7 Hz, 2H), 1.60 – 1.44 (m, 2H), 1.24 (s, 30H), 0.85 (t, J = 6.7 Hz, 3H).

10

Oleic acid

0.00.51.01.52.02.53.03.54.04.55.05.56.0f1 (ppm)

3.00

18.7

9

2.12

3.91

2.03

2.10

0.63

0.82

0.84

0.86

1.23

1.24

1.45

1.47

1.49

1.94

1.96

1.98

2.13

2.16

2.18

2.49

2.49

2.50

2.51

2.51

3.38

5.25

5.26

5.27

5.29

5.30

5.32

5.33

5.35

5.36

11121314f1 (ppm)

0.64

11.9

5

Figure S9. 1H NMR (300 MHz) spectrum of oleic acid (OLA) in deuterated DMSO.

1H NMR (300 MHz, d-DMSO) δ 11.95 (s, 1H), 5.41 – 5.20 (m, 2H), 2.16 (t, J = 7.4 Hz, 2H), 2.06 – 1.86 (m, 4H), 1.55 – 1.38 (m, 2H), 1.23 (d, J = 2.3 Hz, 19H), 0.91 – 0.74 (m, 3H).

11

Octadecene

0.51.01.52.02.53.03.54.04.55.05.56.06.57.07.5f1 (ppm)

2.95

26.8

6

2.00

1.62

0.78

0.87

0.89

0.91

1.27

1.34

1.36

1.38

1.41

1.53

1.97

2.01

2.03

2.06

2.08

4.91

4.91

4.92

4.94

4.95

4.95

4.95

4.96

4.96

4.97

5.02

5.03

5.75

5.77

5.79

5.80

5.81

5.83

5.84

5.85

5.86

5.89

7.26

Figure S10. 1H NMR (300 MHz) spectrum of ODE in deuterated CDCl3.

1H NMR (300 MHz, CDCl3) δ 5.82 (ddt, J = 16.9, 10.2, 6.7 Hz, 1H), 5.12 – 4.76 (m, 2H), 2.12 – 1.92 (m, 2H), 1.60 – 0.97 (m, 27H), 0.89 (t, J = 6.6 Hz, 3H).

12

Table S2. Quantification of the component molar ratio in PODA1

PODA1Reagents Reagents a

mmolComponent b

mmolComponent/PbBr2

b

Molar ratioODABr surfactant 0.081 175ODABr framework 0.20 0.077 1.86

ODE 6.09 0.004 0.09OLA 0.26PbBr2 0.10 0.044 1.00

a Moles used in the synthesis. b Moles of each component in the product calculated by TGA and 1H-RMN; perovskite chemical yield of 44%.

Table S3. Quantification of the component molar ratio in PODA2

PODA2Reagents Reagentsa

mmolComponent b

mmolComponent/PbBr2

b

Molar ratioODABr surfactant 0.053 1.77ODABr framework 0.10 0.053 1.77

ODE 3.00 0.011 0.36PbBr2 0.05 0.030 1.00

a Moles used in the synthesis. b Moles of each component in the product calculated by TGA and 1H-RMN; perovskite chemical yield of 60%

Table S4. Quantification of the component molar ratio in POCA2

POCA2Reagents Reagentsa

mmolComponent b

mmolComponent/PbBr2

b

Molar ratioOCABr surfactant 0.029 0.40OCABr framework

0.200.135 1.82

ODE 6.10 0.003 0.04PbBr2 0.10 0.074 1.00

a Moles used in the synthesis. b Moles of each component in the product calculated by TGA and 1H-RMN; perovskite chemical yield of 74% .

13

X-Ray Photoelectron Spectroscopy Section

PHXA2

525530535540

CPS_O1so1s_1_O1sBackground_O1sEnvelope_O1s

CP

S_O

1s

BE (eV)

POCA2

525530535540

CPS_O1so1s_1_O1sBackground_O1sEnvelope_O1s

CP

S_O

1s

BE (eV)

PODA2

525528531534537540

CPS_O1sO1S_1_O1sBackground_O1sEnvelope_O1s

CP

S_O

1s

BE (eV)

Figure S11. XPS spectra of O1s for PHX2, POCA2 and PODA2

14

PHXA2

280285290295

CPS_C1sc1s_1_C1sc1s_2_C1sBackground_C1sEnvelope_C1s

CP

S_C

1s

BE (eV)

POCA2

280285290295

CPS_C1sc1s_1_C1sc1s_2_C1sBackground_C1sEnvelope_C1s

CP

S_C

1s

BE (eV)

PODA2

280285290295

CPS_C1sc1S_1_C1sC1S_2_C1sBackground_C1sEnvelope_C1s

CP

S_C

1s

BE (eV)

Figure S12. XPS spectra of C1s for PHXA2, POCA2 and PODA2

15

PHXA2

135138141144147150

CPS_Pb4fpb4f7/2_1_Pb4fpb4f5/2_2_Pb4fBackground_Pb4fEnvelope_Pb4f

CP

S_P

b4f

BE (eV)

POCA2

135138141144147150

CPS_Pb4fpb4f7/2_1_Pb4fpb4f5/2_2_Pb4fBackground_Pb4fEnvelope_Pb4f

CP

S_P

b4f

BE (eV)

PODA2

135138141144147150

CPS_Pb4fPb4f7/2_1_Pb4fpb4f5/2_2_Pb4fBackground_Pb4fEnvelope_Pb4f

CP

S_P

b4f

BE (eV)

Figure S13. XPS spectra of Pb4f for PHXA2, POCA2 and PODA2

16

PHXA2

398400402404406

CPS_N1sn1s_1_N1sn1s_2_N1sBackground_N1sEnvelope_N1s

CP

S_N

1s

BE (eV)

POCA2

398400402404406

CPS_N1sN1s_1_N1sn1s_2_N1sBackground_N1sEnvelope_N1s

CP

S_N

1s

BE (eV)

PODA2

398400402404406

CPS_N1sn1s_1_N1sn1S_2_N1sBackground_N1sEnvelope_N1s

CP

S_N

1s

BE (eV)

Figure S14. XPS spectra of N1s for PHXA2, POCA2 and PODA2

17

PHXA2

64666870727476

CPS_Br3d

Background_Br3d

Envelope_Br3d

CP

S_B

r3d

BE (eV)

POCA2

64666870727476

CPS_Br3d

Background_Br3d

Envelope_Br3d

CP

S_B

r3d

BE (eV)

PODA2

64666870727476

CPS_Br3d

Background_Br3d

Envelope_Br3d

CP

S_B

r3d

BE (eV)

Figure S15. XPS spectra of Br3d for PHXA2, POCA2 and PODA2

18

Transmission electron microscopy Section

Figure S16. HRTEM of PHXA2 (a) and POCA2 (b). Scale bar 0.2 µm.

Figure S17. HRTEM of PODA2 in toluene. Scale bar 0.2 µm (a,b), 20 nm (c) and 5 nm (d).

a b

a b

c d

19

X-ray Diffraction Section

Figure S18. Observed (blue) and calculated (red) profiles and difference plot [(Iobs – Icalcd)] (grey) of the X-ray powder diffraction Pawley refinement for PHXA2 (top), POCA2 (middle) and PODA2 (bottom) (λ = Cu Kα, 2θ range 2.0–40.0 °); tick marks indicate peak positions.

20

Figure S19. Observed (blue) and calculated (red) profiles and difference plot [(Iobs – Icalcd)] (grey) of the X-ray powder diffraction Pawley refinement after processing, PODA2np (λ = Cu Kα, 2θ range 2.0–40.0 °); tick marks indicate peak positions.

21

Photostability Studies

0

0.5

1

1.5

2

2.5

3

3.5

4

0 50 100 150 200

PL

(a.u

.)

Time (min)

Figure S20. Photoluminescence of PHXA2 (■), POCA2 (▼) and PODA2 (♦) dispersed in toluene as a function of the irradiation time (exc= 330 nm), PL registered at 411, 409, and 397 nm, respectively, under nitrogen atmosphere.