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MARCH 2022

(UJI - UVEG) J. Sanchez-Diaz, R. S. Sánchez, S. Masi, M. Kreĉmarová, A. O. Alvarez, E. M. Barea, J. Rodriguez-Romero, V. S. Chirvony, J. F. Sánchez-Royo, J. P. Martinez-Pastor and I. Mora-Seró, 

Tin perovskite solar cells with >1300 hours of operational stability in N2 through a synergistic chemical engineering approach

Joule 2022, 6, 861-883


Despite the promising properties of tin-based halide perovskites, one clear limitation is the fast Sn+2 oxidation. Consequently, the preparation of long-lasting devices remains challenging. Here, we report a chemical engineering approach, based on adding Dipropylammonium iodide (DipI) together with a well-known reducing agent, sodium borohydride (NaBH4), aimed at preventing the premature degradation of Sn-HPs. This strategy allows for obtaining efficiencies (PCE) above 10% with enhanced stability. The initial PCE remained unchanged upon 5 h in air (60% RH) at maximum-power-point (MPP). Remarkably, 96% of the initial PCE was kept after 1,300 h at MPP in N2. To the best of our knowledge, these are the highest reported values for Sn-based solar cells. Our findings demonstrate a beneficial synergistic effect when additives are incorporated, highlight the important role of iodide in the performance upon light soaking, and, ultimately, unveil the relevance of controlling the halide chemistry for future improvement of Sn-based perovskite devices.


(UB - UJI) G. Vescio, J. Sanchez-Diaz, J.L. Frieiro, R. S. Sánchez, S. Hernández, A. Cirera, I.Mora-Seró, and B. Garrido  

2D PEA2SnI4 Inkjet-Printed Halide Perovskite LEDs on Rigid and Flexible Substrates,

ACS Energy Letters 2022, 7, 3653–3655


Lead-free PEA2SnI4-based perovskite LEDs are successfully inkjet-printed on rigid and flexible substrates. Red-emitting devices (λmax = 633 nm) exhibit, under ambient conditions, a maximum external quantum efficiency (EQEmax) of 1% with a related brightness of 30 cd/m2 at 10 mA/cm2.


UVEG - UJI) V. S. Chirvony, I. Suárez, Jesus Sanchez-Diaz, R. S. Sánchez, J. Rodríguez-Romero, I. Mora-Seró, and J. P. Martínez-Pastor

Unusual Spectrally Reproducible and High Q-Factor Random Lasing in Polycrystalline Tin Perovskite Films

Advanced Materials 2023, 35, 2208293 (1-10)


An unusual spectrally reproducible near-IR random lasing (RL) with no fluctuation of lasing peak wavelength is disclosed in polycrystalline films of formamidinium tin triiodide perovskite, which have been chemically stabilized against Sn2+ to Sn4+ oxidation. Remarkably, a quality Q-factor as high as ≈104 with an amplified spontaneous emission (ASE) threshold as low as 2 µJ cm−2 (both at 20 K) are achieved. The observed spectral reproducibility is unprecedented for semiconductor thin film RL systems and cannot be explained by the strong spatial localization of lasing modes. Instead, it is suggested that the spectral stability is a result of such an unique property of Sn-based perovskites as a large inhomogeneous broadening of the emitting centers, which is a consequence of an intrinsic structural inhomogeneity of the material. Due to this, lasing can occur simultaneously in modes that are spatially strongly overlapped, as long as the spectral separation between the modes is larger than the homogeneous linewidth of the emitting centers. The discovered mechanism of RL spectral stability in semiconductor materials, possessing inhomogeneous broadening, opens up prospects for their practical use as cheap sources of narrow laser lines.


APRIL 2023

* SOLAR CELLS: New advances in inkjet printing and doctor blade coating of 2D/3D FASnI3 films on flexible substrates. Efficiencies up to 3.3 and 7.9 %, respectively can be obtained under both 1 sun and low light conditions. Modules of 25 cm2 were also fabricated, for which a power efficiency as high as 5.7 % at 1 sun and an impressive 9.4 % at lower light levels  were reached. These results represent the highest reported efficiencies for Sn-based perovskite solar cells and modules fabricated on flexible substrates. Solar cells can be encapsulated with standard procedures to work under ambient conditions. 

* LEDs: First inkjet printed Pb-free perovskite LED (also first in a flexible substrate) emitting at red wavelengths (630 nm),  First orange emitting Pb-free perovskite LED. It was achieved one of the highest brightness in Pb-free perovskite LEDs (close to 300 cd/m2).

* PHOTONICS: Unusual Spectrally Reproducible and High Q-Factor Random Lasing in Polycrystalline FASnI3 Films, Ecofriendly Perovskites (Cs2SnI6) with Giant Self-Defocusing Optical Response, Photoluminescence by two-photon absorption in 2D tin-perovskites, Photoconductive detectors based on 2D and 2D/3D tin-perovskites inkjet printed on glass and flexible substrates with responsivities as high as 10-30 A/W with 5 V bias under 10 nW excitation at 450/785 nm wavelengths.

February 2022

* Synthesis (and inks) of 3D tin-perovskites:  

(From molecular precursors) FASnI3, MASnI3,(FA-MA)SnI3, FASnBr3, MASnBr3,(FA-MA)SnBr3

(NCs) FASnI3, CsSnI3, CsSnBr3   

* Synthesis (and inks) of 2D and 2D/3D tin-perovskites:  

(From molecular precursors) (TEA)2SnI4, PEA2SnI4-xBrx

(NCs) (OLAm)2SnI4, OLAm/PEA)2SnI

* Synthesis (and inks) of double perovskites:

Cs2AgBiBr6, Cs2Ag0.4Na0.6InCl6:Bi, Cs2NaInCl6, Cs2KInCl6

Cs2SnI6, Cs2SnCl6 (Bi3+/Te4+ and Sb3+ doped) 

* Synthesis (and inks) of other halides and perovskite-like materials:

FA3Bi2Br9, Cs3Sb2Br9, Ag2BiI5, Ag3BiI6, Cs2InBr5, Rb3InCl6:Sb


Cs3Cu2I5, Cs3Cu2(Cl/I)5, Cs3Cu2(Cl/I)5:Mn, CsCu2Cl3, Cs3Cu2Cl5.

* Theory: Perovskites, Cs2ZrBr6 and Cs2ZrI6, Cs2TiBr6, Cs2TiI6, Ag2BiI5, Ag3BiI6

* Ink development of metal oxides as inorganic Hole / Electron Transport Layers: 

 InOx, LiNiOx, NiOx, ZnInOx, CsNiOx, NiOx

* SOLAR CELLS: Stable photovoltaic solar cells based on FASnI3 over 1300 h with efficiency  10.6 %, by using appropriated additives. First solar cells fabricated by using doctor blading an inkjet printing deposition of FASnI3 on flexible substrates. 

* LEDs: Selection of Red-Green-Blue emitting materials and preliminary architecture for LEDs. Study of the the FASnI3/C60 heterostructure interface. 

* PHOTONICS: Achievement of Amplified Spontaneous Emission in optical waveguides based on FASnI3 deposited (spin coating and inkjet printing) on flexible substrates. Random lasing can be measured in waveguides and backscattering geometry. The waveguide geometry is ideal to promote photon recycling effect in metal halide perovskites. Some lead-free perovskites exhibits outstanding nonlinear optical properties.

DROP-IT has received funding from the European Union’s Horizon 2020 FET-OPEN research programme under grant agreement No 862656.