Supporting Information

Nickel oxide nanoparticles for efficient hole transport in p-i-n and

n-i-p perovskite solar cells

Zonghao Liu a,b,†, Aili Zhu a,†, Fensha Cai a, LeiMing Tao a, Yinhua Zhou a, Zhixin

Zhao a,*, Qi Chen c, Yi-Bing Cheng a,d, Huanping Zhou b,*

a Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic

Information, Huazhong University of Science and Technology, Wuhan, Hubei

430074, P.R. China

b Department of Materials Science and Engineering, College of Engineering, Peking

University, Beijing 100871, P. R. China

c Department of Materials Science and Engineering, Beijing Institute of Technology,

Beijing 100081, P. R. China

d Department of Materials Engineering, Monash University, Victoria 3800, Australia

† These authors contributed equally to this work.

* Corresponding author:

Z. Zhao (zhixin-zhao@hust.edu.cn);

H. Zhou (hpzhou@pku.edu.cn).

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

mailto:zhixin-zhao@hust.edu.cn

Figure S1 Photographs of the contact angle for the pristine NiOx and NiOx with 5 min

UVO treatment.

290 288 286 284 282

exp. data background

fitting total CC CO OC=O

Binding Energy (eV)

Inte

nsity

(a.u

.)

1200 1000 800 600 400 200

C1s

O1s

Ni2pIn

tens

ity (a

.u.)

Binding Energy (eV)

NiOx

885 880 875 870 865 860 855 850

exp. data backgroundfitting total Ni 2p1/2 Ni 2p2/3 (sat.) Ni 2p1/2 (sat.)

Ni2+ Ni3+ Ni3+

Binding Energy (eV)

Inte

nsity

(a.u

.)

536 534 532 530 528

exp. data background

fitting total O-Ni/C-O-Ni

O=C/Ni-O OH

Binding Energy (eV)

Inte

nsity

(a.u

.)

885 880 875 870 865 860 855 850

exp. data backgroundfitting total Ni 2p1/2 Ni 2p2/3 (sat.) Ni 2p1/2 (sat.)

Ni2+ Ni3+ Ni3+

Binding Energy (eV)

Inte

nsity

(a.u

.)

536 534 532 530 528

exp. data background

fitting total O-Ni/C-O-Ni

O=C/Ni-O OH

Binding Energy (eV)

Inte

nsity

(a.u

.)

290 288 286 284 282

exp. data background

fitting total CC CO OC=O

Binding Energy (eV)

Inte

nsity

(a.u

.)

1200 1000 800 600 400 200

C1s

O1s

Ni2p

Inte

nsity

(a.u

.)

Binding Energy (eV)

NiOx-UVO

a)

b)

c)

d)

e)

f)

g)

h)

NiOx

NiOx -UVO

NiOx NiOx

NiOx -UVO NiOx -UVO

Figure S2. XPS spectra of NiOx and NiOx-UVO films. (a-b) survey scan. (c-d) Ni 2p scan. (e-f) O 1s narrow scan. (g-h) C 1s narrow scan.

Figure S3 X-ray diffraction patterns of perovskite films upon NiOx, NiOx-UVO and

PEDOT:PSS substrate, respectively.

4.0 4.5 5.0 5.5 6.00

5

10

15

ITO/NiOx-UVO E = 5.35 eV

NiOx NiOx-UVO

Coun

ts

Energy (eV)

ITO/NiOx E = 5.24 eV

Figure S4 Work function of ITO/NiOx and ITO/NiOx-UVO samples measured with

UPS.

0 100 200 300 4000

5

10

15

20

Curr

ent d

ensi

ty (m

A/cm

2 )

Time (s)

NiOx NiOx-UVO

8 10 12 14 160

2

4

6

8

10

Coun

ts

PCE (%)

NiOx NiOx-UVO

b)a)

Figure S5 a) Power conversion efficiency distribution for 16 devices measured under

standard one sun AM 1.5G simulated solar irradiation. b) Stabilized output

measurements: current density as a function of time for the NiOx based device (0.82

V) and NiOx-UVO based device (0.87 V) held at a forward bias of maximum output

power point.

0.0 0.2 0.4 0.6 0.8 1.0 1.2-5

0

5

10

15

20

25

Curr

ent d

ensi

ty (m

A/cm

2 )

Voltage (V)

10 mV/s FS 10 mV/s RS 20 mV/s FS 20 mV/s RS 40 mV/s FS 40 mV/s RS

0.0 0.2 0.4 0.6 0.8 1.0 1.2-5

0

5

10

15

20

Curre

nt d

ensi

ty (m

A/cm

2 )

Voltage (V)

10 mV/s FS 10 mV/s RS 20 mV/s FS 20 mV/s RS 40 mV/s FS 40 mV/s RS

a) b)

0.0 0.2 0.4 0.6 0.8 1.0-5

0

5

10

15

20

Cur

rent

den

sity

(mA

/cm

2 )

Voltage (V)

10 m V/s FS 10 m V/s RS 20 m V/s FS 20 m V/s RS 40 m V/s FS 40 m V/s RS

c)

NiOx NiOx-UVO

PEDOT:PSS

Figure S6 J-V curve of NiOx (a), NiOx-UVO (b) and PEDOT:PSS (c) based device

measured under different directions (forward scan, FS, from -0.2 V to 1.2 V, reverse

scan, RS, from 1.2 V to -0.2 V) and different scan rate (10, 20, 40 mV s-1,

respectively).

Table S1 Device performance of the NiOx, NiOx-UVO and PEDOT:PSS devices

measured under simulated AM 1.5 (100 mW cm-2) conditions with under different

directions (forward scan, FS, from -0.2 V to 1.2 V, reverse scan, RS, from 1.2 V to -

0.2 V) and different scan rate (10, 20, 40 mV s-1, respectively).

Device scan

direction

scan rate

(mV s-1)

Voc

(V)

Jsc (mA

cm-2)

FF

(%)

PCE

(%)

FS 10 1.03 20.58 74.7 15.89

RS 10 1.03 20.66 74.2 15.90

FS 20 1.04 21.41 72.3 16.03

RS 20 1.04 20.87 73.6 16.04

FS 40 1.04 21.26 71.4 15.82

NiOx-UVO

RS 40 1.04 21.08 73.6 16.20

FS 10 1.04 16.31 66.1 11.30

RS 10 1.04 16.73 68.4 12.00

FS 20 1.04 16.56 66.3 11.41

RS 20 1.04 16.83 69.0 12.06

FS 40 1.04 16.89 66.5 11.62

NiOx

RS 40 1.04 16.89 69.6 12.18

FS 10 0.948 17.38 74.14 12.22

RS 10 0.938 17.26 75.37 12.20

FS 20 0.936 17.55 74.61 12.26

PEDOT:PSS RS 20 0.936 17.33 74.91 12.16

FS 40 0.916 17.59 76.77 12.37

RS 40 0.916 17.45 75.64 12.10

50 100 150 2000.0

0.2

0.4

0.6

0.8

1.0

Nor

mal

ized

PC

E

Time (h)

spiro-OMeTAD NiOx without NiOx

Figure S7 The efficiency of unencapsulated devices stored in ambient air with the

humidity of 45−50% under dark.

Figure S8 The images of water drop on the surface of perovskite layer and perovskite/NiOx layer 1 min later.