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
(OPEN ACCESS)
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.
SEPTEMBER 2022
(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
(OPEN ACCESS)
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.
NOVEMBER 2022
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)
(OPEN ACCESS)
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.
