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
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
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
ABSTRACT
Organic–inorganic lead halide perovskite has recently emerged as an efficient absorber material for solution process photovoltaic (PV) technology, with certified efficiency exceeding 25%. The development of low-temperature (LT) processing is a challenging topic for decreasing the energy payback time of perovskite solar cell (PSC) technology. In this context, the LT planar n–i–p architecture meets all the requirements in terms of efficiency, scalability, and processability. However, the long-term stability of the LT planar PSC under heat and moisture stress conditions has not been carefully assessed. Here, a detailed study on thermal and moisture stability of large-area (1 cm2) LT planar PSCs is presented. In particular, the key role in thermal stability of potassium iodide (KI) insertion in the perovskite composition is demonstrated. It is found that defect passivation of triple-cation perovskite by KI doping inhibits the halide migration induced by thermal stress at 85 °C and delays the formation of degradation subproducts. T80, defined as the time when the cell retains 80% of initial efficiency, is evaluated both for reference undoped devices and KI-doped ones. The results show that T80 increases 3 times when KI doping is used. Moreover, an HTL-free architecture where the Au top electrode is replaced with low-T screen-printable carbon paste is proposed. The combination of the carbon-based HTL-free architecture and KI-doped perovskite permits T80 to increase from 40 to 414 h in unsealed devices.
Authors:
Emanuele Calabrò, Fabio Matteocci, Barbara Paci, Lucio Cinà, Luigi Vesce, Jessica Barichello, Amanda Generosi, Andrea Reale, Aldo Di Carlo
Publication Date: 26 June 2020
https://doi.org/10.1021/acsami.0c05878
ACS Chemistry for Life
ABSTRACT
Reducing the energy demand and dependency on fossil fuels is crucial for improving the sustainability of greenhouses, which are the most energy intensive systems in the agricultural sector. Renewable technologies represent a key option to meet the greenhouse energy demands. Agrivoltaics has recently emerged as a strategy to combine farming activity and power generation through photovoltaics (PV). However, PV systems retrofitting needs to consider the interactions with the existing greenhouse structure, as well as the energy requirements of the equipment for climate control. The influences of PV shading on agronomic parameters have also to be carefully considered. Firstly, this review examines the response of plants to the light and the fundamental aspects of greenhouse facilities. Then, the state-of-the-art of PV systems applied to greenhouses is thoroughly analysed. Simulation studies and experimental works are examined to highlight the effects of PV technologies and module arrangements on energy production and plant growth. Particular attention is devoted to new PV technologies, i.e. organic, dye-sensitized and perovskite solar cells, because of their semi-transparency and flexibility, allowing the easy integration of PV modules into existing or newly conceived greenhouse structures.
The review has highlighted that the new PV technologies have an enormous potential due to the possibility of tuning their spectral features according to the characteristics of plants and to the capability of optimizing the use of solar energy into high-tech greenhouses. Shading through these innovative systems has also demonstrated to create a suitable atmosphere for crop growth especially in hot and tropical regions.
Authors:
Luca La Notte, Lorena Giordano, Emanuele Calabrò, Roberto Bedini, Giuseppe Colla, Giovanni Puglisi, Andrea Reale
Publication date: 25 September 2020
https://doi.org/10.1016/j.apenergy.2020.115582
Science Direct
ABSTRACT
Carbon nanotube/polymer composites have recently received considerable attention for thermoelectric (TE) applications. The TE power factor can be significantly improved by forming composites with carbon nanotubes. However, the formation of a uniform and well-ordered nanocomposite film is still challenging because of the creation of agglomerates and the uneven distribution of nanotubes. Here, we developed a facile, efficient, and easy-processable route to produce uniform and aligned nanocomposite films of P3HT and carbon nanotube forest (CNTF). The electrical conductivity of a pristine P3HT film was improved from ∼10–7 to 160 S/cm thanks to the presence of CNTF. Also, a further boost in TE performance was achieved using two additives, lithium bis(trifluoromethanesulfonyl) imide (LiTFSI) and tert-butylpyridine. By adding the additives to P3HT, the degree of interchain order increased, which facilitated the charge transport through the composite. Under the optimal conditions, the incorporation of CNTF and additives led to values of the Seebeck coefficient, electrical conductivity, and power factor up to rising 92 μV/K, 130 S/cm, and 110 μW/m K2, respectively, at a temperature of 344.15 K. The excellent TE performance of the hybrid films originates from the dramatically increased electrical conductivity and the improved Seebeck coefficient by CNTF and additives, respectively.
Authors:
Saeed Mardi, Khabib Yusupov, Patricia M. Martinez, Anvar Zakhidov, Alberto Vomiero and Andrea Reale
Publication Date: January 7, 2021
https://doi.org/10.1021/acsomega.0c02663
ACS Publications
ABSTRACT
We present Z-Type Dye Sensitized Solar Modules (DSSMs) with screen printed graphene-based vertical interconnects. This prevents corrosion of interconnects in contact with electrolytic species, unlike conventional Ag interconnects. By enlarging the width of single cells, or by increasing the number of cells, we get an enhancement of the aperture power conversion efficiency ∼+12% with respect to Ag-based modules, with 1000 h stability under 85 °C stress test. This paves the way to original design layouts with decreased dead area and increased generated power per aperture area.
Authors:
Paolo Mariani, Antonio Agresti, Luigi Vesce, Sara Pescetelli, Alessandro Lorenzo Palma, Flavia Tomarchio, Panagiotis Karagiannidis, Andrea C. Ferrari and Aldo Di Carlo
https://doi.org/10.1021/acsaem.0c01960
ACS Publications
Publication Date: December 31, 2020