4-tert-butylpyridine for DMSO-free Tin Perovskite

Giuseppe Nasti^a, Mahmoud Hussein Aldamasy^b, Antonio Abate^a^,^b

^aDepartment of Chemical, Materials and Production Engineering, University of Naples Federico II, Naples, Italy

^bDepartment of Novel Materials and Interfaces for Photovoltaic Solar Cells, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz, 1, Berlin, Germany

NIPHO
Proceedings of International Conference on Perovskite Thin Film Photovoltaics and Perovskite Photonics and Optoelectronics (NIPHO23)

Pavia, Italy, 2023 May 15th - 16th

Organizers: Giulia Grancini and Silvia Colella

Oral, Giuseppe Nasti, presentation 004
DOI: https://doi.org/10.29363/nanoge.nipho.2023.004
Publication date: 3rd April 2023

Metal-halide perovskites have attracted extensive interest due to the high efficiencies obtained in photovoltaic devices.[1] The main drawback of this technology is the presence of lead which is a well-known and dreaded environmental pollutant. Also at very low concentrations, it is the cause of many diseases in humans, animals and plants. Moreover, the ionic nature of Pb²⁺ is at the origin of a very efficient uptake rate from the ground to plants.[2] For this reason many different approaches have been studied to tackle this concern, and the substitution of lead with tin is probably the most promising.[3],[4] Tin is an element of the same group of lead and can take its place in the perovskite lattice. Compared to lead, tin, is much more sensible to oxidation and can easily be oxidized from Sn²⁺ to Sn⁴⁺.[5],[6] On one side this behaviour is at the origin of the lesser toxicity of tin respect to lead but on the other side it represents a severe limitation during the processing of the material, as the formation of Sn⁴⁺ reduces the photovoltaic device performances. DMSO, which is one of the most used solvents for tin perovskites processing, has been identified as a source of oxidation due to a redox side reaction. Here we show that 4-tert-Butylpyridine (tBP) is a promising substitute for DMSO as it can mimic and exceed its complexation ability to tin iodide.[7] As SnI₂ has stronger Lewis acidity than PbI₂ it reacts faster with the organic salts leading to rapid crystallization of perovskite crystals which leads to a poor morphology with many pinholes. The stronger interaction between SnI₂ and tBP slows the crystallization process leading to the formation of a smooth defect-free perovskite film. We show that, together with the better morphology, perovskite synthesised using tBP possess better electronic properties in terms of defect density and hole density. Tin perovskite prepared using our procedure can be used to prepare photovoltaic device with a maximum PCE of 8.3% in a reproducible manner.

References:

[1] Saliba, M. et al. Cesium-containing triple cation perovskite solar cells: improved stability, reproducibility and high efficiency. Energy Environ. Sci. 9, 1989–1997 (2016).

[2] Li, J. et al. Biological impact of lead from halide perovskites reveals the risk of introducing a safe threshold. Nat Commun 11, 310 (2020).

[3] Jiang, X. et al. One-Step Synthesis of SnI2·(DMSO)x Adducts for High-Performance Tin Perovskite Solar Cells. J. Am. Chem. Soc. 143, 10970–10976 (2021)

[4] Yu, B.-B. et al. Heterogeneous 2D/3D Tin-Halides Perovskite Solar Cells with Certified Conversion Efficiency Breaking 14%. Advanced Materials 33, 2102055 (2021).

[5] Saidaminov, M. I. et al. Conventional Solvent Oxidizes Sn(II) in Perovskite Inks. ACS Energy Lett. 5, 1153–1155 (2020)

[6] Pascual, Jorge, et al. "Origin of Sn (II) oxidation in tin halide perovskites." Materials Advances 1.5 (2020): 1066-1070

[7] Nasti, Giuseppe, and Antonio Abate. "Tin halide perovskite (ASnX3) solar cells: a comprehensive guide toward the highest power conversion efficiency." Advanced Energy Materials 10.13 (2020): 1902467.

Acknowledgements:

This work was supported by the Italian Ministry of Ecological Transition in the framework of the Operating Agreement with ENEA for Mission Innovation. Funding from the European Research Council (Grant Number, 804519) is acknowledged.

nanoGe is a prestigious brand of successful science conferences that are developed along the year in different areas of the world since 2009. Our worldwide conferences cover cutting-edge materials topics like perovskite solar cells, photovoltaics, optoelectronics, solar fuel conversion, surface science, catalysis and two-dimensional materials, among many others.

MATSUS

Previously nanoGe Spring Meeting (NSM) and nanoGe Fall Meeting (NFM), MATSUS is a multiple symposia conference focused on a broad set of topics of advanced materials preparation, their fundamental properties, and their applications, in fields such as renewable energy, photovoltaics, lighting, semiconductor quantum dots, 2-D materials synthesis, charge carriers dynamics, microscopy and spectroscopy semiconductors fundamentals, etc.

International Conference on Hybrid and Organic Photovoltaics

International Conference on Hybrid and Organic Photovoltaics (HOPV) is celebrated yearly in May. The main topics are the development, function and modeling of materials and devices for hybrid and organic solar cells. The field is now dominated by perovskite solar cells but also other hybrid technologies, as organic solar cells, quantum dot solar cells, and dye-sensitized solar cells and their integration into devices for photoelectrochemical solar fuel production.

Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics

The main topics of the Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP) are discussed every year in Asia-Pacific for gathering the recent advances in the fields of material preparation, modeling and fabrication of perovskite and hybrid and organic materials. Photovoltaic devices are analyzed from fundamental physics and materials properties to a broad set of applications. The conference also covers the developments of perovskite optoelectronics, including light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.

International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics

The International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics (NIPHO) is the best place to hear the latest developments in perovskite solar cells as well as on recent advances in the fields of perovskite light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.