Rohit D. Chavan, Bartłomiej Bończak, Joanna Kruszyńska, Apurba Mahapatra, Muhammad Ans, Jan Nawrocki, Kostiantyn Nikiforow, Pankaj Yadav, Jan Paczesny, Faranak Sadegh, Muhittin Unal, Seckin Akin, and Daniel Prochowicz

Chemistry of Materials 2023 35 (19), 8309-8320

DOI: 10.1021/acs.chemmater.3c01995

This study introduces a novel azahomofullerene (AHF-4) as an interlayer in perovskite solar cells (PSCs), enhancing charge transfer and film quality while reducing recombination. AHF-4 outperforms the standard fullerene derivative PCBM, achieving higher efficiency (21.43%) and better stability under light and heat, promising advancements in PSC performance and durability.

How Litos Lite and Litos were used

The photovoltaic performance was evaluated using a Fluxim Litos Lite setup, equipped with a Wavelabs Sinus LS2 solar simulator with AM 1.5 spectrum for excitation.

Aging tests were also performed using a Fluxim Litos setup, and 1 Sun equivalent illumination with no UV component, holding the substrates at 45 ± 5 °C in a N2 atmosphere and using an MPP tracking algorithm.

Montecucco, R., Pica, G., Romano, V., De Boni, F., Cavalli, S., Bruni, G., Quadrivi, E., De Bastiani, M., Prato, M., Po, R. and Grancini, G. (2023),

Sol. RRL 2300358.

https://doi.org/10.1002/adfm.202306040

All-inorganic perovskites show potential for creating stable and high-performing perovskite solar cells (PSCs). But, the high annealing temperature required for CsPbI3 stabilization limits its scalability for industrial production. This research introduces a method to stabilize CsPbI3ₓBrx perovskite at a reduced annealing temperature of 180°. This is achieved by using dimethylammonium (DMA) additives and bromide, facilitating the conversion to CsPbI3ₓBrx. Solar cells produced this way reached a power conversion efficiency (PCE) of 14.86%, outperforming the reference device. Using different halides in DMA salt for higher temperature annealing also proved beneficial, yielding an impressive PCE of 16.23%. This method, by lowering processing temperature, extends the utility of all-inorganic PSCs for industrial use and temperature-sensitive materials.

How Litos Lite was used

The stability measurements were performed at the MPP under N2 inert atmosphere and ambient temperature using Litos Lite coupled with a solar simulator continuously illuminating the devices. The spectrum used for the stability measurements was the same as the current density–voltage measurements.

Juanita Hidalgo, Lahoucine Atourki, Ruipeng Li, Andrés-Felipe Castro-Méndez, Sanggyun Kim, Emmet A. Sherman, Alexander S. Bieber, Meng-ju Sher, Lea Nienhaus, Carlo A.R. Perini, Juan-Pablo Correa-Baena,

Materials Today, Volume 68, 2023, Pages 13-21, ISSN 1369-7021,

https://doi.org/10.1016/j.mattod.2023.06.010

Interfacial treatments using bulky cations on 3D lead halide perovskites (LHPs) have led to over 25% power conversion efficiencies, but the reasons for this boost remain unclear. This study zeroes in on formamidinium lead iodide (FAPI) perovskites and shows that phenethylammonium iodide (PEAI) prevents the FAPI from changing into less desirable hexagonal forms in air exposure. Using advanced analytical methods, researchers discovered that untreated FAPI films predominantly show these undesired hexagonal phases. However, when coated with PEAI, FAPI films exhibit improved carrier lifetimes and photoconductivity. Such PEAI-treated FAPI solar cells can achieve up to 20.2% efficiency and 1.14 V open circuit voltages, marking one of the top performances for FAPI cells without extra cations.

How Litos Lite was used

Solar cell performance was evaluated under a solar simulator LITOS LITE from Fluxim, with AM1.5 spectrum, same light intensity for the maximum power point tracking for 180 s. The current density–voltage (JV) curve was measured in a forward and reverse bias at a scan rate of 50 mV/s. The cells were masked for measurement with a pixel area of 0.0625 cm2. Nitrogen was flown in the measurement chamber during characterization.

Larini, V., Ding, C., Faini, F., Pica, G., Bruni, G., Pancini, L., Cavalli, S., Manzi, M., Degani, M., Pallotta, R., De Bastiani, M., Ma, C.-Q., Grancini, G

Adv. Funct. Mater. 2023, 2306040.

https://doi.org/10.1002/adfm.202306040

Transparent conductive oxide (TCO)-coated glasses are a costly and environmentally impactful part of perovskite solar cells (PSCs), accounting for 56% of their total cost and 96% of their carbon footprint. Recycling TCO glasses from old PSC modules can reduce both their cost and energy payback time. In this study, tin oxide (SnO2)-coated indium tin oxide glasses are refurbished using eco-friendly dimethyl sulfoxide as a solvent. The reclaimed substrates are used to create new-generation PSCs with the same high efficiency of 22.6%, and even higher average efficiency, thanks to surface modifications and trap passivation on the SnO2/perovskite interface.

How Litos Lite was used

Stability measurements were conducted by coupling a WavelabsSINUS-70 solar simulator with a Fluxim Litos Lite module and perform-ing maximum power point tracking for 1000 h under an N2atmosphere at1 sun illumination, employing a shadow mask of 1.25 mm2active area.

Juanita Hidalgo, Yu An, Dariia Yehorova, Ruipeng Li, Joachim Breternitz, Carlo A.R. Perini, Armin Hoell, Pablo P. Boix, Susan Schorr, Joshua S. Kretchmer, and Juan-Pablo Correa-Baena

Chemistry of Materials 2023 35 (11), 4181-4191

DOI: 10.1021/acs.chemmater.3c00075

This scientific article investigates the factors that determine crystallographic orientation in lead bromide perovskites. The researchers show that the solvent and organic A-site cation play a critical role in preferred orientation of the thin films. The results reveal that the solvent, specifically dimethylsulfoxide (DMSO), influences the early stages of crystallization and induces preferred orientation by preventing colloidal particle interactions. Additionally, the choice of A-site cation, such as methylammonium or formamidinium, affects the degree of preferred orientation. Density functional theory calculations suggest that the difference in surface energy between the (100) and (110) facets is the reason for the varying degrees of preferred orientation. Besides, the researchers observe that the choice of A-site cation impacts ion density and accumulation, leading to increased hysteresis in solar cells. Overall, this study highlights the importance of solvent and A-site cation in determining crystallographic orientation and its impact on the electronic and ionic properties of solar cells.

How Litos Lite & Paios were used

LITOS LITE was used to measure the current density-voltage (J-V) characteristics of the solar cells. The J-V curves were obtained by scanning voltage in the range from 1.4 to -0.5 V with a scan speed of 50 mV·s-1 first in reverse and then in forward scan directions. The active area of the device was 0.128 cm2, and a black metal mask with an aperture area of 0.0625 cm2 was used to define the illuminated area.

Impedance Spectroscopy: #PAIOS was used to perform Impedance Spectroscopy (IS) on complete solar cells at room temperature under one sun illumination and in ambient air. The measurements were performed at five different offset voltages spaced from 0 V to the open circuit.

Carlo Andrea Riccardo Perini, Esteban Rojas-Gatjens, Magdalena Ravello, Andrés-Felipe Castro-Mendez, Juanita Hidalgo, Yu An, Sanggyun Kim, Barry Lai, Ruipeng Li, Carlos Silva-Acuña, and Juan-Pablo Correa-Baena

Adv. Mater. 2022, 34, 2204726

https://doi.org/10.1002/adma.202204726

This study investigates the impact of bulky-cation-modified interfaces on the stability of halide perovskite solar cells, which has not been extensively explored. The research demonstrates the thermal instability of these interface layers used in state-of-the-art solar cells and reveals changes in the chemical composition and structure of the films under thermal stress, which affects charge-carrier dynamics and device operation. The type of cation used for surface treatment also affects the extent of these changes, with long carbon chains providing more stable interfaces. The study emphasizes the importance of prolonged annealing of the treated interfaces to enable reliable reporting of performance and inform the selection of different bulky cations.

Device Characterization: The photovoltaic performance was evaluated using a Fluxim Litos Lite setup, equipped with a Wavelabs Sinus-70 AAA solar simulator with AM1.5 spectrum for excitation.

Aging tests were performed using a Fluxim Litos setup, using 1 Sun equivalent illumination with no UV-component, holding the substrates at 55 °C in a N2 atmosphere and using an MPP tracking algorithm. Every 12 h, a J–V scan in reverse and forward direction was automatically acquired.

Andrés-Felipe Castro-Méndez, Carlo A. R. Perini, Juanita Hidalgo, Daniel Ranke, Jacob N. Vagott, Yu An, Barry Lai, Yanqi Luo, Ruipeng Li, and Juan-Pablo Correa-Baena

ACS Applied Materials & Interfaces Article ASAP

DOI: 10.1021/acsami.2c02036

Thermal evaporation is a promising deposition technique to scale up perovskite solar cells (PSCs) to large areas, but the lack of understanding of the mechanisms that lead to high quality evaporated methylammonium lead triiodide (MAPbI3) films gives rise to devices with efficiencies lower than those obtained by spin coating.

In this paper the researchers investigate the role of Sr and Ca additives to CsFA-PbI solar cells on performance.

Litos Lite was used to perform JV scan under 1 sun illumination.

Hurriyet Yuce, Diana LaFollette, Mustafa M. Demir, Carlo A.R. Perini, Juan-Pablo Correa- Baena

Sol. RRL 2100999.

doi.org/10.1002/solr.202100999

In the article the researchers investigate the crystal formation of co-evaporated MAI -PbI2 films at different temperature on the Perovskite Solar Cell (PSC) performance and correlate it to the occurrence of different phases.

The J-V curves of the devices were measured in a forward and reverse bias under the solar simulator (Fluxim, Litos Lite) with AM1.5 spectrum at a scan rate of 15 mV/s.

Perini, Carlo and Rojas-Gatjens, Esteban and Ravello, Magdalena and Castro Mendez, Andres Felipe and Hidalgo, Juanita and An, Yu and Li, Ruipeng and Silva-Acuña, Carlos and Correa-Baena, Juan-Pablo

doi.org/10.2139/ssrn.3921344

10 Sep 2021

The impact on device stability of the bulky cation-modified interfaces in halide perovskite solar cells is not well-understood. In this paper the research team demonstrate the thermal instability of the bulky cation interface layers used in some of the highest performing solar cells to date.

The photovoltaic performance was evaluated using a Fluxim Litos Lite setup, equipped with a Wavelabs Sinus-70 AAA solar simulator with AM1.5 spectrum for excitation. The current voltage (J-V) characteristics were acquired with forward and reverse scans at a scan rate of 50 mV s-1. The stabilized power output was acquired using a maximum power point tracking algorithm for 60 s. Devices were not preconditioned before measurement. Masking was used during the measurement, defining a pixel area of 0.0625 cm2. Nitrogen was flown in the measurement chamber during characterization. No temperature control was applied. Aging tests were performed using a Fluxim Litos setup, using 1 Sun equivalent illumination with no UV-component, holding the substrates at 55 °C in a N2 atmosphere and using a maximum power point tracking algorithm. Every 12 h a J-V scan in reverse and forward direction was automatically acquired.