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Single-crystalline TiO2 nanoparticles for stable and efficient perovskite modules


Despite the remarkable progress in power conversion efficiency of perovskite solar cells, going from individual small-size devices into large-area modules while preserving their commercial competitiveness compared with other thin-film solar cells remains a challenge. Major obstacles include reduction of both the resistive losses and intrinsic defects in the electron transport layers and the reliable fabrication of high-quality large-area perovskite films. Here we report a facile solvothermal method to synthesize single-crystalline TiO2 rhombohedral nanoparticles with exposed (001) facets. Owing to their low lattice mismatch and high affinity with the perovskite absorber, their high electron mobility and their lower density of defects, single-crystalline TiO2 nanoparticle-based small-size devices achieve an efficiency of 24.05% and a fill factor of 84.7%. The devices maintain about 90% of their initial performance after continuous operation for 1,400 h. We have fabricated large-area modules and obtained a certified efficiency of 22.72% with an active area of nearly 24 cm2, which represents the highest-efficiency modules with the lowest loss in efficiency when scaling up.

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Fig. 1: Effects of electron mobility of TiO2-based ETL and interfacial defect density of TiO2/perovskite interface on the FF loss.
Fig. 2: Morphology and characterization of single-crystalline TiO2 nanoparticles.
Fig. 3: Comparison of NP- and SC-based device photovoltaic performance and characterization.
Fig. 4: Interfacial charge transfer dynamics of perovskite films based on the NP and SC substrates.
Fig. 5: Module architecture and performance, and small-sized device’s stability.

Data availability

The data for this study are available from the corresponding authors upon reasonable request. Source data are provided with this paper.

Code availability

The finite-element method codes used in this work are available from the corresponding authors upon reasonable request.


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This work was supported by the National Key R&D Program of China (2018YFB1500101), the 111 Project (no. B16016) and the National Natural Science Foundation of China (no. U1705256 and no. 51961165106). V.D. and P.D. acknowledge the financial support by the Deutsche Forschungsgemeinschaft in the frame of the Priority Program SPP 2196 (project DY 18/14–1). We thank the Swiss National Science Foundation for financial support of the SOLAR4D project (project no. 200020L_1729/1) and Luxembourg Fonds National de la Recherche (‘SUNSPOT’, no. 11244141 and INTER, no. 16/11534230).

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Authors and Affiliations



Y.D. and B.D. conceived and made the experiment. Y.D. synthesized the single-crystalline TiO2 nanoparticles. H.K. performed the XPS, UPS and SEM characterization. O.J.U. conducted the HIM-SIMS characterization with supervision from J.-N.A. T.G. performed the UHV-AFM and KPFM measurement with supervision from A.R. Z.Y. and J.S. simulated the influence of trap state density and electron mobility of TiO2 on the whole photovoltaic performance. Y.L. conducted the UPS, Hall effect measurement and spherical aberration electron microscopy with supervision from G.Y. H.H. performed the steady-state, transient absorption spectroscopy and transient absorption spectroscopy measurement with supervision from W.D. C.L., Y.Y. and X.Z. conducted SCLC and CV measurements. M.A. and P.D. made the time-resolved microwave conductivity measurements. V.S. performed OCVD measurements with supervision from V.D. R.W. performed the TRPL characterization. Y.D. and B.D. wrote the first draft of the manuscript, and all authors contributed feedback and comments. G.Y., J.W. S.D., P.J.D. and M.K.N. directed and supervised the research.

Corresponding authors

Correspondence to Guanjun Yang, Songyuan Dai, Paul J. Dyson or Mohammad Khaja Nazeeruddin.

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Supplementary information

Supplementary Information

Supplementary Notes 1–4, Figs. 1–34, Tables 1–8, experimental details and refs. 1–82.

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Supplementary Video 1

Water immersion test.

Source data

Source Data Fig. 1

Simulation data.

Source Data Fig. 2

Unprocessed EELS data.

Source Data Fig. 3

Unprocessed JV data, EQE data and so on.

Source Data Fig. 4

Unprocessed time-resolved photoluminescence and transient absorption spectra data.

Source Data Fig. 5

Unprocessed JV and EQE data, and statistical source data.

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Ding, Y., Ding, B., Kanda, H. et al. Single-crystalline TiO2 nanoparticles for stable and efficient perovskite modules. Nat. Nanotechnol. 17, 598–605 (2022).

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