Supporting Information

In-situ Synthesis of Metal Nanoparticle-Polymer Composites and

Their Application as Efficient Interfacial Materials for Both Polymer

and Planar Heterojunction Perovskite Solar Cells

Zhicheng Hu, Sheng Dong, Qifan Xue, Rongguo Xu, Hin-Lap Yip,* Fei Huang* and Yong Cao

Fig. S1 Picture of Au doped PN4N solution (in methanol) (left) and Au NPs capped by sodium citrate solution (in

water) (right) after stored for 3 months. Obviously, the solution of Au NPs capped by sodium citrate started to

precipitated and the Au doped PN4N solution stayed clear.

(a)

5%

5% 10%

15% 20%

(b)

(c)

Fig. S2 Three-dimensional AFM images of doped PN4N film(a), large TEM images (b)and size distribution of the

Au nanoparticles (10% and 20%) (c).

Fig. S3 AFM topography of the pristine undoped PN4N film, a moderately root mean square roughness (RMS) of

1.46 nm was obtained.

400 500 600 700

0.01

0.02

0.03

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0.05

0.06

0.07

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0.09

0.10

Abso

rban

ce

wavelenth (nm)

Au@sodium Citrate

Fig. S4 UV-visible absorption spectra of Au NPs capped by citrate sodium. ( Au NPs capped by citrate sodium was

synthesized according to the reported literature,[46] and was directly mixed into PEDOT:PSS. It was estimated that

the diameter of synthesized Au NPs was ~40 nm from corresponding UV-visible absorption spectra)

300 400 500 600 700 800 9000.00

0.05

0.10

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0.25

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Abso

rban

ce

Wavelenth (nm)

PN4N+PCDTBT:PCBM PN4N(Au)+PCDTBT:PCBM

Fig. S5 UV-visible absorption spectra of PCDTBT:PC71BM thin films deposited on PN4N films with or without Au

NPs

Fig. S6 The statistic distributions of the perovskite solar cell performance

Fig. S7 Normalized absorption spectrum of pure perovskite film