Hybrid Interfacial ETL Engineering using PCBM-SnS2 for High-

Performance p-i-n Structured Planar Perovskite Solar Cells

Pramila Patila, Dilpreet Singh Manna, Umesh T. Nakateb, Yoon-Bong Hahnb,

Sung-Nam Kwona, and Seok-In Naa,

aProfessional Graduate School of Flexible and Printable Electronics, LANL - JBNU

Engineering Institute - Korea, Jeonbuk National University, 664-14, Baekje-daero, Deokjin-

gu, Jeonju-si, Jeollabuk-do, 561-756, Republic of Korea

bSchool of Semiconductor and Chemical Engineering, Solar Energy Research Center,

Jeonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju-si, 54896, Jeollabuk-do,

Republic of Korea

Corresponding author. Tel.: +82 63 270 4465; fax: +82 63 270 2341

E-mail address: nsi@jbnu.ac.kr (S.-I. Na)

Figure S1: Schematics for SnS2 synthesis and exfoliation process.

Figure S2: Full XPS survey for synthesized SnS2

Table S3: XRD analysis of synthesized SnS2

UPS data analysis

Parameter Standard values/Formula

(hkl)/2θ

Estimatedvalues

Crystallite size (D) (nm) Scherrer’sformula

D= K .λβ . cosθ

(001),(010),(011)(110),(111),(020)

3.8, 4.5, 5.2,8.7, 5.9, 6.1 Average = ~ 5.7

d – spacing (Å)JCPDS – Card no. 23-0677

5.85,3.135, 2.763,1.81, 1.729, 1.567

(001),(010),(011)(110),(111),(020)

5.95, 3.137, 2.765,1.82, 1.748, 1.564

Diffraction peak2θ (degree)

15.133, 28.447, 32.373, 50.375, 52.9, 58.868

(001),(010),(011)(110),(111),(020)

14.86, 28.42, 32.35,50, 52.24, 58.99

Dislocation density (lines/m2) X 1016

δ = 1/D2 (001),(010),(011)(110),(111),(020)

6.93,4.94,3.7,1.32, 2.87,2.69

Texture coefficient TC

TC hkl=

Ihkl

I 0

1N ∑ I hkl

I0

(001),(010),(011)(110),(111),(020)

0.31, 1.73, 0.15,0.7, 0.58, 1.68

The Fermi level of PCBM and PCBM-SnS2 can be calculated using the equation as shown

below (1)

EF = Ecut-off - 21.21 eV (1)

Where, EF is the Fermi level, Ecut-off is cut-off binding energy, and 21.21 eV is emission

energy of Helium irradiation. The Ecut-off values for PCBM and PCBM- SnS2 are 16.71 eV and

16.85 eV, respectively. The Fermi level of PCBM and PCBM-SnS2 are determined to be -4.5

eV and -4.36 eV, respectively. The valence band (EVB) is determined by equation

EVB = EF - Eedge (2)

Where, Eedge is Fermi edge. The Eedge of PCBM and PCBM-SnS2 are 1.38 eV and 1.58 eV,

respectively. Hence, the EVB of PCBM and PCBM-SnS2 are -5.88 eV and -5.99 eV,

respectively.

Figure: UPS spectra of perovskite layer

Figure S4: (a) EDS for PCBM-SnS2 deposited on perovskite layer and (b) EDS for pure PCBM. FESEM analysis of (c) Perovskite (d) PCBM and (e) PCBM-SnS2

Figure S5: J-V characteristics for PCBM and PCBM-SnS2 measured at forward and reverse scan directions.

Figure S6: The water contact angle of PCBM and PCBM-SnS2 deposited on perovskite layer

Figure S7: TEM image of (a) PCBM and (b) PCBM-SnS2 layer

Table S8: Summary on inorganic interfacial layer based PSCs with different structures

Structure Device configuration PCE (%) Reference

Planar/inverted ITO/NiO/Perovskite/PCBM-SnS2/ZnO/Ag 19.95 Present work

Planar/inverted ITO/PTAA/ Perovskite /PCBM/CMB-vTA/AZO/Ag

17.15 [1]

Planar/inverted FTO/NiO/GO/ Perovskite /GO-Li:TiOx/Al 11.2 [2]

Planar/inverted ITO/NiOx/ Perovskite /PCBM-F8Bt/Ag 15 [3]

Planar/inverted ITO/PEDOT:PSS/Perovskite/PCBM/BCP/Ag 17.26 [4]

Planar/inverted FTO/Cu-NiOx/Perovskite/PCBM/CeOx/Ag 16.70 [5]

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