Analysis of the O2 passivation effects on MAPbI3 and MAPbBr3 by transient photovoltage technique in fresh and aged solar cells

Due to the low temperature fabrication process and reduced hysteresis effect, inverted p-i-n structured perovskite solar cells (PSCs) with the PEDOT:PSS as the hole transporting layer and PCBM as the electron transporting layer have attracted considerable attention. However, the energy barrier at the interface between the PCBM layer and the metal electrode, which is due to an energy level mismatch, limits the electron extraction ability. In this work, an inorganic aluminum-doped zinc oxide (AZO) interlayer is inserted between the PCBM layer and the metal electrode so that electrons can be collected efficiently by the electrode. It is shown that with the help of the PCBM/AZO bilayer, the power conversion efficiency of PSCs is significantly improved, with negligible hysteresis and improved device stability. The UPS measurement shows that the AZO interlayer can effectively decrease the energy offset between PCBM and the metal electrode. The steady state photoluminescence, time-resolved photoluminescence, transient photocurrent, and transient photovoltage measurements show that the PSCs with the AZO interlayer have a longer radiative carrier recombination lifetime and more efficient charge extraction efficiency. Moreover, the introduction of the AZO interlayer could protect the underlying perovskite, and thus, greatly improve device stability.

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Plasmonic Effects on Bulk Heterojunction Polymer Solar Cells: A Transient Photovoltage and Differential Charging Study

Science of Advanced Materials ◽

10.1166/sam.2017.3114 ◽

2017 ◽

Vol 9 (8) ◽

pp. 1435-1439 ◽

Cited By ~ 3

Author(s):

Soon Yie Kok ◽

Zong-Chun Hsieh ◽

Chun-Hsien Chou ◽

Shun-Shing Yang ◽

Ming-Kai Chuang ◽

...

Keyword(s):

Solar Cells ◽

Bulk Heterojunction ◽

Polymer Solar Cells ◽

Transient Photovoltage ◽

Plasmonic Effects

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Origin of Degradation in Perovskite Solar Cells by Intensity Modulated Photovoltage Spectroscopy Measurement (IMVS)

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1028.133 ◽

2021 ◽

Vol 1028 ◽

pp. 133-137

Author(s):

Adhita Asma Nurunnizar ◽

Alvin Fariz ◽

Herman ◽

Rahmat Hidayat

Keyword(s):

Solar Cells ◽

Charge Carrier ◽

Conversion Efficiency ◽

Cell Structure ◽

Perovskite Solar Cells ◽

Nyquist Plot ◽

Frequency Range ◽

Intensity Modulated ◽

Transient Photovoltage ◽

Lower Frequency Range

Perovskite solar cells (PSCs) based on lead halide perovskite have attracted much attention owing to the fast development of their power conversion efficiency (PCE) from 3.8% to 25%. Various factors play important roles in affecting the conversion efficiency of PSCs, such as charge carrier generation, transport, recombination, and collection. In addition, the presence of interfacial defects has also a crucial effect in charge carrier transfer and recombination processes. However, the origin and mechanism of interfacial charge recombinations in PSCs are still not comprehensively investigated. For that purpose, we have performed intensity-modulated photovoltage spectroscopy (IMVS) and transient photovoltage (TPV) measurements of PSCs, which were fabricated with FTO/c-TiO2/mp-TiO2/Perovskite/PTAA/Au cell structure. The solar cell (J-V) characteristics of the PSCs on the day-1, day-2, day-3, and day-6 after the cell fabrication, indicating a significant degradation of the cell with time. The Nyquist plots of IMVS measurement on the same day as the J-V measurement seem to be composed of two semicircles at a lower frequency range and a higher frequency range. The semicircle at the lower frequency range enlarged on the day-6 measurement, but the semicircle at higher frequency decreased. The change of this Nyquist plot is in agreement with a significant decrease in the J-V curves. The semicircle at lower frequency may be assigned to the ion diffusion or migration. Therefore, cell degradation may be caused by the liberation of ions (including iodide) from the surface of the perovskite crystal structure. It then increases recombination loss due to back charge transfer from TiO2 to perovskite as indicated by the changing of the semicircle at high frequency into a smaller semicircle. Therefore, the present results reemphasize that the improvement of PSC stability needs the prevention of ions liberations from the surface by introducing passivation substances. In addition, the results also show the practical usefulness of IMVS for inspecting PSC degradation due to such an ion liberation process.

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A combined transient photovoltage and impedance spectroscopy approach for a comprehensive study of interlayer degradation in non-fullerene acceptor organic solar cells

Nanoscale ◽

10.1039/c9nr02337b ◽

2019 ◽

Vol 11 (22) ◽

pp. 10872-10883 ◽

Cited By ~ 5

Author(s):

Adam Pockett ◽

Harrison Ka Hin Lee ◽

Brendan L. Coles ◽

Wing C. Tsoi ◽

Matthew J. Carnie

Keyword(s):

Solar Cells ◽

Impedance Spectroscopy ◽

Active Layer ◽

Organic Solar Cells ◽

Transient Photovoltage ◽

Comprehensive Study

Transient photovoltage and impedance spectroscopy measurements reveal how degradation affects both the active layer and the interlayer in OPV devices.

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Overcoming the Limitations of Transient Photovoltage Measurements for Studying Recombination in Organic Solar Cells

Solar RRL ◽

10.1002/solr.201900581 ◽

2020 ◽

Vol 4 (5) ◽

pp. 1900581 ◽

Cited By ~ 1

Author(s):

Mohammed Azzouzi ◽

Philip Calado ◽

Andrew M. Telford ◽

Flurin Eisner ◽

Xueyan Hou ◽

...

Keyword(s):

Solar Cells ◽

Organic Solar Cells ◽

Transient Photovoltage

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Transient Photovoltage Measurements in Nanocrystal-Based Solar Cells

The Journal of Physical Chemistry C ◽

10.1021/acs.jpcc.6b03695 ◽

2016 ◽

Vol 120 (23) ◽

pp. 12900-12908 ◽

Cited By ~ 13

Author(s):

Weyde M. M. Lin ◽

Deniz Bozyigit ◽

Olesya Yarema ◽

Vanessa Wood

Keyword(s):

Solar Cells ◽

Transient Photovoltage

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Recombination in Annealed and Nonannealed Polythiophene/Fullerene Solar Cells: Transient Photovoltage Studies versus Numerical Modeling

The Journal of Physical Chemistry Letters ◽

10.1021/jz1001506 ◽

2010 ◽

Vol 1 (9) ◽

pp. 1432-1436 ◽

Cited By ~ 127

Author(s):

Rick Hamilton ◽

Christopher G. Shuttle ◽

Brian O’Regan ◽

Thomas C. Hammant ◽

Jenny Nelson ◽

...

Keyword(s):

Numerical Modeling ◽

Solar Cells ◽

Transient Photovoltage

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Study on the Change in Photovoltage by Control of Cell Gap in Dye-Sensitized Solar Cells

Journal of Solar Energy Engineering ◽

10.1115/1.4001151 ◽

2010 ◽

Vol 132 (2) ◽

Cited By ~ 2

Author(s):

Chaehyeon Lee ◽

Weekyung Kang ◽

Min Jae Ko ◽

Kyoungkon Kim ◽

Nam-Gyu Park

Keyword(s):

Solar Cells ◽

Electrochemical Impedance ◽

Dye Sensitized Solar Cells ◽

Energy Conversion Efficiency ◽

Open Circuit ◽

Electrolyte System ◽

Counter Electrodes ◽

Dye Sensitized ◽

Transient Photovoltage ◽

Sensitized Solar Cells

Photo-electrochemical properties of dye-sensitized solar cells (DSSCs) were investigated by changing the gap between working and counter electrodes. The open-circuit voltage (VOC) of DSSCs was significantly increased from 616 mV to 776 mV by about 26% with 1-methyl-3-butyl imidazolium iodide (BMII) based electrolyte and from 428 mV to 513 mV by 20% with lithium iodide (LiI) based electrolyte as the cell gap increased from 16 μm to 224 μm. From the electrochemical impedance spectroscopy, it was found that the resistance of the electrolyte was increased as the cell gap widened. This resulted in the reduction in the dark current associated with the VOC enhancement. The transient photovoltage spectroscopic measurement confirmed that the time constant for charge recombination between TiO2 and electrolyte became slower as the cell gap of the DSSC with LiI electrolyte increased, which could be an additional reason for the VOC enhancement. The optimal cell gap was determined to be around 31.3 μm for the BMII electrolyte system, and around 75.5 μm for the LiI electrolyte system in terms of the energy-conversion efficiency.

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