As the market uptake of perovskite solar cells (PSCs) is projected to grow rapidly, this clean energy technology will play an increasingly important role in reducing the global carbon footprint. However, one of the major barriers to its full commercialization is the presence of toxic lead (Pb), which enables the current record in photoconversion efficiency but risks being released into the environment when subjected to water or rain. Here we show that Pb leakage can be prevented by applying a transparent titanium dioxide (TiO2) sponge that allows for an efficient Pb sequestration of 58 ng cm−2 nm−1. Already an essential material for PSCs, the additional use of TiO2 through a scalable and solvent-free sputtering process promises extra cost benefits and higher sustainability. Further demonstration of the sponge application with desired thickness on ready-to-use devices, glass and polymeric foils enforces the practical value of the current approach. Our study provides a sustainable solution to one of the environmental and health risks of PSCs and would accelerate their practical applications.
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This activity was partially supported at National Research Council (CNR) by the national projects, BEYOND NANO Upgrade (Univocal Project Code (CUP) G66J17000350007) and VertiGrow (CUP B15F21004410005). This work has been partially funded by the European Union (NextGeneration EU), through the MUR-PNRR project SAMOTHRACE – Sicilian MicronanoTech Research and Innovation Center (ECS00000022, CUP B63C22000620005). This work was supported by a grant from the Swiss National Supercomputing Centre (CSCS) under project ID s963 and s1167. We thank T. Quinn for her kind proofreading work. We also thank V. Privitera (CNR-IMM) for supporting this research.
The authors declare no competing interests.
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Supplementary Figs. 1–14, Tables 1–6 and Notes 1–6.
Data of forward-scan current density–voltage curve in Supplementary Fig. 1.
Data of photovoltaic parameters over time in Supplementary Fig. 2.
Data of transmittance vs photon energy in Supplementary Fig. 3.
Data of absorption coefficient and transmittance vs photon energy in Supplementary Fig. 7a,b.
Data of absorption coefficient vs photon energy in Supplementary Fig. 14.
Data of reverse-scan current density–voltage curve in Fig. 1f.
Data of Pb concentration vs time and Pb-adsorption capability vs TiO2 thickness in Fig. 2b,c.
Data of energy dispersive X-ray graph in Fig. 4f.
Data of Kohn–Sham total energy in Fig. 5e,f.
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Valastro, S., Smecca, E., Mannino, G. et al. Preventing lead leakage in perovskite solar cells with a sustainable titanium dioxide sponge. Nat Sustain 6, 974–983 (2023). https://doi.org/10.1038/s41893-023-01120-w
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