Modulated Photocurrent Spectroscopy Study of the Electronic Transport Properties of Working Organic Photovoltaics: Degradation Analysis

Electronic transport measurement using modulated photocurrent (MPC) spectroscopy is demonstrated herein in working organic photovoltaics (OPVs) before and after AM1.5G irradiation. OPVs with bulk heterojunction (BHJ) using prototypical donor and acceptor materials, poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1–2-b:4,5-b′]dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl] = hieno [3–4-b]thiophenediyl]] (PTB7) and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM), were fabricated. The OPVs had inverted structures (BHJs are formed on transparent conductive oxide substrates). The photovoltaic performance of PTB7:PC71BM OPVs was characterized and the best power conversion efficiency was obtained at PTB7 content of 40 wt%. Electron and hole mobility were determined with MPC spectroscopy in PTB7:PC71BM OPVs and were well balanced at PTB7 content of 40 wt%. Degradation of the photovoltaic performance of PTB7:PC71BM OPVs with PTB7 content of 40 wt% caused by AM1.5G irradiation was studied. MPC spectroscopy showed that the well-balanced mobility was not affected by AM1.5G irradiation. The degradation of OPVs was not due to changes in the electronic transport properties, but mainly to the reduced short circuit current (Jsc) and fill factor (FF). The origin of this reduction is discussed.

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Electronic Transport Properties of the Azobenzene-Based Optical Molecular Switch with Different Substituents

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.284-286.816 ◽

2011 ◽

Vol 284-286 ◽

pp. 816-819

Author(s):

Cai Juan Xia ◽

Han Chen Liu ◽

Jing Wang

Keyword(s):

Transport Properties ◽

Electronic Transport ◽

Density Functional ◽

Molecular Switch ◽

Functional Theory ◽

Electronic Transport Properties ◽

Switching Performance ◽

Donor And Acceptor ◽

Donor Acceptor ◽

Theoretical Results

By applying nonequilibrium Green’s function formalism combined first-principles density functional theory, we investigate the electronic transport properties of the azobenzene -based optical molecular switch with different substituents. Theoretical results show that the donor/acceptor substituent plays an important role in the electronic transport of molecular devices. The switching performance can be improved to some extent through suitable donor and acceptor substituents.

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Enhanced Power Conversion Efficiency of P3HT : PC71BM Bulk Heterojunction Polymer Solar Cells by Doping a High-Mobility Small Organic Molecule

International Journal of Photoenergy ◽

10.1155/2015/982064 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 6

Author(s):

Hanyu Wang ◽

Xiao Wang ◽

Pu Fan ◽

Xin Yang ◽

Junsheng Yu

Keyword(s):

Solar Cells ◽

Power Conversion Efficiency ◽

Conversion Efficiency ◽

Polymer Solar Cells ◽

Short Circuit ◽

Power Conversion ◽

Photovoltaic Performance ◽

Acid Methyl Ester ◽

High Mobility ◽

Short Circuit Current

The effect of molecular doping with TIPS-pentacene on the photovoltaic performance of polymer solar cells (PSCs) with a structure of ITO/ZnO/poly(3-hexylthiophene-2,5-diyl) (P3HT) : [6,6]-phenyl C71-butyric acid methyl ester (PC71BM) : TIPS-pentacene/MoOx/Ag was systematically investigated by adjusting TIPS-pentacene doping ratios ranged from 0.3 to 1.2 wt%. The device with 0.6 wt% TIPS-pentacene exhibited the enhanced short-circuit current and fill factor by 1.23 mA/cm2and 7.8%, respectively, resulting in a maximum power conversion efficiency of 4.13%, which is one-third higher than that of the undoped one. The photovoltaic performance improvement was mainly due to the balanced charge carrier mobility, enhanced crystallinity, and matched cascade energy level alignment in TIPS-pentacene doped active layer, resulting in the efficient charge separation, transport, and collection.

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Improved Performance of Ternary Solar Cells by Using BODIPY Triads

Materials ◽

10.3390/ma13122723 ◽

2020 ◽

Vol 13 (12) ◽

pp. 2723 ◽

Cited By ~ 2

Author(s):

Sompit Wanwong ◽

Weradesh Sangkhun ◽

Pisist Kumnorkaew ◽

Jatuphorn Wootthikanokkhan

Keyword(s):

Solar Cells ◽

Short Circuit ◽

Power Conversion ◽

Photovoltaic Performance ◽

Acid Methyl Ester ◽

Short Circuit Current ◽

Ternary Blend ◽

Acid Methyl ◽

Boron Dipyrromethene ◽

Improved Performance

Two boron dipyrromethene (BODIPY) triads, namely BODIPY-1 and BODIPY-2, were synthesized and incorporated with poly-3-hexyl thiophene: (6,6)-phenyl-C61-butyric acid methyl ester (PCBM) P3HT:PCBM. The photovoltaic performance of BODIPY:P3HT:PCBM ternary solar cells was increased, as compared to the control binary solar cells (P3HT:PCBM). The optimized power conversion efficiency (PCE) of BODIPY-1:P3HT:PCBM was improved from 2.22% to 3.43%. The enhancement of PCE was attributed to cascade charge transfer, an improved external quantum efficiency (EQE) with increased short circuit current (Jsc), and more homogeneous morphology in the ternary blend.

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Investigation of the Electronic Transport Properties of Nanocrystalline Particulate TiO2Electrodes by Intensity-Modulated Photocurrent Spectroscopy

The Journal of Physical Chemistry B ◽

10.1021/jp962226n ◽

1997 ◽

Vol 101 (14) ◽

pp. 2716-2722 ◽

Cited By ~ 137

Author(s):

P. E. de Jongh ◽

D. Vanmaekelbergh

Keyword(s):

Transport Properties ◽

Electronic Transport ◽

Electronic Transport Properties ◽

Intensity Modulated ◽

Photocurrent Spectroscopy ◽

Intensity Modulated Photocurrent Spectroscopy

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ELECTRONIC TRANSPORT PROPERTIES OF SILICON NANOWIRE CAGE

10.1615/ihtc16.mpe.022406 ◽

2018 ◽

Author(s):

Shenqiu Mo ◽

Dengke Ma ◽

Lina Yang ◽

Meng An ◽

Zhiyu Liu ◽

...

Keyword(s):

Transport Properties ◽

Electronic Transport ◽

Silicon Nanowire ◽

Electronic Transport Properties

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Optical Absorption Enhancement in Polymer BHJ thin Film Using Ag Nanostructures: A Simulation Study

Current Nanoscience ◽

10.2174/1573413715666190125163438 ◽

2020 ◽

Vol 16 (4) ◽

pp. 556-567

Author(s):

Asma Khalil ◽

Zubair Ahmad ◽

Farid Touati ◽

Mohamed Masmoudi

Keyword(s):

Absorption Spectrum ◽

Solar Cell ◽

Methyl Ester ◽

Butyric Acid ◽

Organic Solar Cell ◽

Short Circuit ◽

Acid Methyl Ester ◽

Short Circuit Current ◽

Acid Methyl ◽

Butyric Acid Methyl Ester

Background: The photo-absorption and light trapping through the different layers of the organic solar cell structures are a growing concern now-a-days as it affects dramatically the overall efficiency of the cells. In fact, selecting the right material combination is a key factor in increasing the efficiency in the layers. In addition to good absorption properties, insertion of nanostructures has been proved in recent researches to affect significantly the light trapping inside the organic solar cell. All these factors are determined to expand the absorption spectrum and tailor it to a wider spectrum. Objective: The purpose of this investigation is to explore the consequence of the incorporation of the Ag nanostructures, with different sizes and structures, on the photo absorption of the organic BHJ thin films. Methods: Through a three-dimensional Maxwell solver software, Lumerical FDTD, a simulation and comparison of the optical absorption of the three famous organic materials blends poly(3- hexylthiophene): phenyl C71 butyric acid methyl ester (P3HT:PCBM), poly[N-9″-heptadecanyl-2,7- carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole)]: phenyl C71 butyric acid methyl ester (PCDTBT:PCBM) and poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b′]dithiophene)-alt- 4,7-(2,1,3-benzothiadiazole)]: phenyl C71 butyric acid methyl ester (PCDPDTBT:PCBM) has been conducted. Furthermore, FDTD simulation study of the incorporation of nanoparticles structures with different sizes, in different locations and concentrations through a bulk heterojunction organic solar cell structure has also been performed. Results: It has been demonstrated that embedding nanostructures in different locations of the cell, specifically in the active layer and the hole transporting layer had a considerable effect of widening the absorption spectrum and increasing the short circuit current. The effect of incorporation the nanostructures in the active layer has been proved to be greater than in the HTL. Furthermore, the comparison results showed that, PCDTBT:PCBM is no more advantageous over P3HT:PCBM and PCPDTBT:PCBM, and P3HT:PCBM took the lead and showed better performance in terms of absorption spectrum and short circuit current value. Conclusion: This work revealed the significant effect of size, location and concentration of the Ag nanostructures while incorporated in the organic solar cell. In fact, embedding nanostructures in the solar cell widen the absorption spectrum and increases the short circuit current, this result has been proven to be significant only when the nanostructures are inserted in the active layer following specific dimensions and structures.

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The Influence of the Thickness of Compact TiO2 Electron Transport Layer on the Performance of Planar CH3NH3PbI3 Perovskite Solar Cells

Materials ◽

10.3390/ma14123295 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3295

Author(s):

Andrzej Sławek ◽

Zbigniew Starowicz ◽

Marek Lipiński

Keyword(s):

Solar Cells ◽

Electron Transport ◽

Short Circuit ◽

Photovoltaic Performance ◽

Perovskite Solar Cells ◽

Precursor Solution ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Transport Layer ◽

Electron Transport Layer

In recent years, lead halide perovskites have attracted considerable attention from the scientific community due to their exceptional properties and fast-growing enhancement for solar energy harvesting efficiency. One of the fundamental aspects of the architecture of perovskite-based solar cells (PSCs) is the electron transport layer (ETL), which also acts as a barrier for holes. In this work, the influence of compact TiO2 ETL on the performance of planar heterojunction solar cells based on CH3NH3PbI3 perovskite was investigated. ETLs were deposited on fluorine-doped tin oxide (FTO) substrates from a titanium diisopropoxide bis(acetylacetonate) precursor solution using the spin-coating method with changing precursor concentration and centrifugation speed. It was found that the thickness and continuity of ETLs, investigated between 0 and 124 nm, strongly affect the photovoltaic performance of PSCs, in particular short-circuit current density (JSC). Optical and topographic properties of the compact TiO2 layers were investigated as well.

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Improved thermoelectric transport properties of Ge4Se3Te through dimensionality reduction

Journal of Materials Chemistry C ◽

10.1039/d0tc04537c ◽

2021 ◽

Author(s):

H. H. Huang ◽

Xiaofeng Fan ◽

Wei Tao Zheng ◽

David J. Singh

Keyword(s):

Dimensionality Reduction ◽

Transport Properties ◽

Electronic Transport ◽

Thermoelectric Transport ◽

Electronic Transport Properties ◽

Thermoelectric Transport Properties

Layered semiconducting Ge4Se3Te shows unusual bonding that suggests the possibility of unusual transport that may be favorable for thermoelectrics. We investigated the electronic transport properties in relation to thermoelectricity of...

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