ANALYSIS OF THE EFFICIENCY LOSSES IN HYBRID PEROVSKITE/PTAA SOLAR CELLS WITH DIFFERENT MOLECULAR WEIGHTS: MORPHOLOGY VERSUS KINETICS

ABSTRACT

The PTAA polymer is often used as a hole transport material (HTM) for high-efficiency perovskite solar cells (PSCs). However, there are great differences within the solar cell efficiencies reported. Herein, we show that when increasing PTAA molecular weight (MW) from 10 to 115 kDa, the power conversion efficiency also increases. We analyze how the differences in MW influence the interfacial carrier losses in the PSCs under operando conditions using advanced photoinduced spectroscopic techniques. Moreover, we compare kinetics and structural/morphological effects by studying different PTAA MW films. Our results show that the observed differences within the reported PSC efficiencies are due to the differences in carrier recombination kinetics, which are influenced by the differences in the polymer MW.

Authors:

Narges Yaghoobi Nia, Maria Méndez, Barbara Paci, Amanda Generosi, Aldo Di Carlo, Emilio Palomares

https://doi.org/10.1021/acsaem.0c00956

ACS Applied Energy Materials

https://pubs.acs.org/doi/abs/10.1021/acsaem.0c00956

FABRICATION OF HIGH EFFICIENCY, LOW-TEMPERATURE PLANAR PEROVSKITE SOLAR CELLS VIA SCALABLE DOUBLE-STEP CRYSTAL ENGINEERING DEPOSITION METHOD FULLY OUT OF GLOVE BOX

ABSTRACT

In this work the scalable Crystal Engineering approach was successfully applied to fabricate the CH3NH3PbI3 absorbing layer on low-temperature planar SnO2 under atmospheric conditions (fully out of glove-box). Photovoltaic characterization showed high-reproducible hysteresis-free planar perovskite solar cells with a maximum power conversion efficiency of 17.6%. The photophysical properties of the PSCs, evaluated by transient photovoltage and photocurrent analysis, showed the excellent capability of SnO2 to extract charge for perovskite. Non-encapsulated n-i-p planar solar cells indicated promising stability under atmospheric conditions, maintaining 90% of the initial efficiency for more than 1000 h. We demonstrate that the scalable air insensitive crystal engineering method is a promising approach for industrialization and fabrication of high efficiency, air-stable, and low-temperature planar perovskite solar cells with high reproducibility fabrication.

Authors:

Shiva Navazani, Narges Yaghoobi Nia, Mahmoud Zendehdel, Ali Shokuhfar, Aldo Di Carlo

https://doi.org/10.1016/j.solener.2020.05.084

Solar Energy Volume 206, August 2020, Pages 181-187

https://www.sciencedirect.com/science/article/abs/pii/S0038092X20305831

POLYMER/INORGANIC HOLE TRANSPORT LAYER FOR LOW-TEMPERATURE-PROCESSED PEROVSKITE SOLAR CELLS

ABSTRACT

In the work we introduce a hysteresis-free low-temperature planar PSC, composed of a poly (3-hexylthiophene)(P3HT)/CuSCN bilayer as a hole transport layer (HTL) and a mixed cation perovskite absorber. Proper adjustment of the precursor concentration and thickness of the HTL led to a homogeneous and dense HTL on the perovskite layer. This strategy not only eliminated the hysteresis of the photocurrent, but also permitted power conversion efficiencies exceeding 15.3%. The P3HT/CuSCN bilayer strategy markedly improved the life span and stability of the non-encapsulated PSCs under atmospheric conditions and accelerated thermal stress. The device retained more than 80% of its initial efficiency after 100 h (60% after 500 h) of continuous thermal stress under ambient conditions.

Authors:

Neda Irannejad, Narges Yaghoobi Nia, Siavash Adhami, Enrico Lamanna, Behzad Rezaei, Aldo Di Carlo

https://doi.org/10.3390/en13082059

MDPI Journals Energies Vol. 13 Issue 8

https://www.mdpi.com/1996-1073/13/8/2059

THIAZOLO[5,4-D]THIAZOLE-BASED ORGANIC SENSITIZERS WITH IMPROVED SPECTRAL PROPERTIES FOR APPLICATION IN GREENHOUSE-INTEGRATED DYE-SENSITIZED SOLAR CELLS

ABSTRACT

Organic photosensitizers especially designed for producing semitransparent dye-sensitized solar cells (DSSCs) for greenhouse integration were prepared by introduction of different heterocyclic moieties into the thiazolo[5,4-d]thiazolemolecular scaffold. The aim was that of improving their light absorption capability in the green part of the visible spectrum while maintaining a good transparency in the blue and red regions, where the photosynthetic response is maximized. A short and efficient synthetic approach, featuring two consecutive C-H activation reactions in a one-pot procedure as key steps, was used. Based on their spectroscopic and electrochemical characterization, two of dyes prepared appeared especially suitable for greenhouse-integrated photovoltaics. The corresponding semitransparent DSSCs yielded 5.6-6.1% power conversion efficiencies, which were largely superior to those provided by other organic dyes previously proposed for the same application.

Authors:

Alessio Dessì, Massimo Calamante, Adalgisa Sinicropi, Maria Laura Parisi, Luigi Vesce, Paolo Mariani, Babak Taheri, Manuela Ciocca, Aldo Di Carlo, Lorenzo Zani, Alessandro Mordini, Gianna Reginato

https://doi.org/10.1039/D0SE00124D

Sustainable Energy & Fuels 2020

LOW TEMPERATURE PROCESS OF HOMOGENEOUS AND PIN-HOLE FREE PEROVSKITE LAYERS FOR FULLY COATED PHOTOVOLTAIC DEVICES UP TO 256 CM2 AREA AT AMBIENT CONDITION

ABSTRACT

The versatility of printing/coating technologies together with the development of new hybrid and organic materials permit to revolutionize the photovoltaic (PV) research and manufacture. Among the new PV concept, perovskite solar cell technology has ascended top efficiencies in few years. The low-cost perspective of this III-GEN PV is however achievable only at industrial production levels. To this end, we developed a simple yet scalable process for production of monolithic Perovskite solar modules (PSMs). Here we use the doctor blade coating technique assisted by a hot air flow. The basic setup is easy to build and permits to obtain a homogeneous and repeatable deposition of the layers forming the PSM. By applying this fabrication method at ambient condition, we fabricated a low temperature module up to 40 cm2 with a conversion efficiency above 11% and a perovskite layer up to 256 cm2, both based on a pinhole free one-step (without any anti-solvent technique) method, demonstrating the scaling up capability of the optimised process.

Authors: 

Luigi Vesce, Maurizio Stefanelli, Aldo Di Carlo

https://doi.org/10.1109/ISAECT47714.2019.9069678

2019 International Symposium on Advanced Electrical and Communication Technologies (ISAECT)

SOLUTION-BASED HETEROEPITAXIAL GROWTH OF STABLE MIXED CATION/ANION HYBRID PEROVSKITE THIN FILM UNDER AMBIENT CONDITION VIA A SCALABLE CRYSTAL ENGINEERING APPROACH

ABSTRACT

The performance of perovskite solar cells is under direct control of the perovskite film quality and controlling the crystalinity and orientation of solution-processed perovskite film is a fundamental challenge. In this study, we present a scalable fabrication process for heteroepitaxial growth of mixed-cation hybrid perovskites (FA1-x-yMAxCsy)Pb(I1-xBrx)3 in ambient atmospheric condition by using a Crystal Engineering (CE) approach. Smooth and mesoporous thin film of pure crystalline intermediate phase of PbX2.2DMSO is formed by deposition of supersaturated lead/cesium halides solution. Kinetically fast perovskite nucleation is achieved by rapid intercalation of formamidinium iodide (FAI) and methylammonium bromide (MABr) into the intermediate layer trough solvent assisted SN1 ligand exchange. Finally, heteroepitaxially perovskite growth is accomplished via Volmer−Weber crystal growth mechanism. All the layers are deposited under atmospheric condition (relative humidity (RH) 50–75%) with high reproducibility for various device and module dimensions. In particular, perovskite solar modules (Pmax ~550 mW) are successfully fabricated by blade coating under atmospheric condition. The CE approach remarkably improves the device performance by reaching a power conversion efficiency of 18.4% for small area (0.1 cm2), 16.5% on larger area (1 cm2) devices, and 12.7% and 11.6% for blade-coated modules with an active area of 17 and 50 cm2, respectively. Non-encapsulated triple cation solar cells and modules show promising stability under atmospheric shelf life and light soaking conditions.

Authors:

Narges Yaghoobi Nia, Fabrizio Giordano, Mahmoud Zendehdel, Lucio Cinà, Alessandro Lorenzo Palma, Pier Gianni Medaglia, Shaik Mohammed Zakeeruddin, Michael Grätzel, Aldo Di Carlo 

https://doi.org/10.1016/j.nanoen.2019.104441

"Nano Energy", Volume 69, March 2020, 104441

https://www.sciencedirect.com/science/article/abs/pii/S2211285519311589#!