Special Issue "Polymers for Energy Applications"

A special issue of Polymers (ISSN 2073-4360).

Deadline for manuscript submissions: closed (30 September 2018)

Special Issue Editors

Guest Editor
Prof. Dr. Tzi-yi Wu

Department of Chemical Engineering and Materials Engineering, National Yunlin University of Science and Technology, Douliou, Taiwan
Website | E-Mail
Interests: solar energy polymers; electrochromic polymers; light-emitting diodes; solar cells; opto-electronic functional polymer materials
Guest Editor
Prof. Dr. Dong Hwan Wang

School of Integrative Engineering, Chung-Ang University, Seoul 06974, Korea
Website | E-Mail
Interests: Organic Electronics (OPV, OPD, and Perovskite); Device Physics; Nanomaterials (Synthesis and Characterization); Nanomorphology Control; Nanopatterning; Oxide Materials; Stamping-Transfer Nanotechnology

Special Issue Information

Dear Colleagues,

Polymers and their composites have recently received significant interest as electrode materials and electrolytes for high-performance supercapacitors, fuel cells, lithium-ion batteries, dye-sensitized solar cells, and electrochromic devices.

The potential use of polymer materials for devices has been investigated intensely over the past few decades. In particular, conjugated polymers show semiconductor-like behavior and have emerged as intriguing materials for the fabrication of flexible, large-area, and low power and low cost electronic devices. Moreover, the high absorption coefficients of polymers and polymer composites and the possibility of varying the band gap through molecular engineering have opened up new options for multicolor electrochromic devices and solar-energy conversion.

This Special Issue covers the synthesis, physicochemical properties, optical and electrochemical characterization, and applications of polymer materials in energy technologies. In addition, feature articles and review papers with regard to the progresses of polymer materials in a particular area are welcomed.

Prof. Dr. Tzi-yi Wu
Prof. Dr. Dong Hwan Wang
Guest Editor

Manuscript Submission Information

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Keywords

  • Polymer-based organic photovoltaic devices
  • Polymer blend electrolytes
  • Polymer hydrogel based materials for fuel cells
  • Hybrid polymer-inorganic composites
  • Synthesis of polymer composites for energy storage applications
  • Polymer membranes for energy applications
  • Polymers for energy storage capacitor applications
  • Polymer-based organic batteries
  • Optical and electrochemical characterizations of polymers

Published Papers (15 papers)

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Research

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Open AccessArticle
Polymer/Fullerene Blend Solar Cells with Cadmium Sulfide Thin Film as an Alternative Hole-Blocking Layer
Polymers 2019, 11(3), 460; https://doi.org/10.3390/polym11030460
Received: 24 December 2018 / Revised: 20 January 2019 / Accepted: 25 January 2019 / Published: 11 March 2019
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Abstract
In this work, chemical bath-deposited cadmium sulfide (CdS) thin films were employed as an alternative hole-blocking layer for inverted poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) bulk heterojunction solar cells. CdS films were deposited by chemical bath deposition and their thicknesses were [...] Read more.
In this work, chemical bath-deposited cadmium sulfide (CdS) thin films were employed as an alternative hole-blocking layer for inverted poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) bulk heterojunction solar cells. CdS films were deposited by chemical bath deposition and their thicknesses were successfully controlled by tailoring the deposition time. The influence of the CdS layer thickness on the performance of P3HT:PCBM solar cells was systematically studied. The short circuit current densities and power conversion efficiencies of P3HT:PCBM solar cells strongly increased until the thickness of the CdS layer was increased to ~70 nm. This was attributed to the suppression of the interfacial charge recombination by the CdS layer, which is consistent with the lower dark current found with the increased CdS layer thickness. A further increase of the CdS layer thickness resulted in a lower short circuit current density due to strong absorption of the CdS layer as evidenced by UV-Vis optical studies. Both the fill factor and open circuit voltage of the solar cells with a CdS layer thickness less than ~50 nm were comparatively lower, and this could be attributed to the effect of pin holes in the CdS film, which reduces the series resistance and increases the charge recombination. Under AM 1.5 illumination (100 mW/cm2) conditions, the optimized PCBM:P3HT solar cells with a chemical bath deposited a CdS layer of thickness 70 nm and showed 50% power conversion efficiency enhancement, in comparison with similar solar cells with optimized dense TiO2 of 50 nm thickness prepared by spray pyrolysis. Full article
(This article belongs to the Special Issue Polymers for Energy Applications)
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Open AccessArticle
Effect of Solvents on the Electrical and Morphological Characteristics of Polymer Solar Cells
Polymers 2019, 11(2), 228; https://doi.org/10.3390/polym11020228
Received: 19 January 2019 / Revised: 28 January 2019 / Accepted: 29 January 2019 / Published: 1 February 2019
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Abstract
The nanoscale morphology of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C71. butyric acid methylester (PCBM) blend film is affected by various parameters such as the solvent, coating, and thermal annealing conditions. We investigated the effect of solvents on the performance of inverted solar [...] Read more.
The nanoscale morphology of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C71. butyric acid methylester (PCBM) blend film is affected by various parameters such as the solvent, coating, and thermal annealing conditions. We investigated the effect of solvents on the performance of inverted solar cells based on the active layer of a P3HT:PCBM bulk heterojunction. P3HT and PCBM (weight ratio 1:0.8) were dissolved in chlorobenzene (CB) and dichlorobenzene (DCB). The difference in the volatility characteristics of the solvents resulted in different P3HT crystallite morphologies. The difference in the P3HT:PCBM film morphology was systemically investigated via atomic force microscopy, ultraviolet (UV)-visible absorption spectroscopy, X-ray diffraction, and electrical impedance spectroscopy. The DCB solvent lead to better P3HT crystallinity and device performance. For example, the short-circuit current density (JSC) and the power conversion efficiency (PCE) of the device using DCB (9.89 mA/cm2 and 3.62%, respectively) were larger than those (9.12 mA/cm2 and 3.01%) of the device using CB. Full article
(This article belongs to the Special Issue Polymers for Energy Applications)
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Open AccessArticle
Dissolved Gases Forecasting Based on Wavelet Least Squares Support Vector Regression and Imperialist Competition Algorithm for Assessing Incipient Faults of Transformer Polymer Insulation
Polymers 2019, 11(1), 85; https://doi.org/10.3390/polym11010085
Received: 24 December 2018 / Accepted: 28 December 2018 / Published: 8 January 2019
Cited by 4 | PDF Full-text (5036 KB) | HTML Full-text | XML Full-text
Abstract
A solution for forecasting the dissolved gases in oil-immersed transformers has been proposed based on the wavelet technique and least squares support vector machine. In order to optimize the hyper-parameters of the constructed wavelet LS-SVM regression, the imperialist competition algorithm was then applied. [...] Read more.
A solution for forecasting the dissolved gases in oil-immersed transformers has been proposed based on the wavelet technique and least squares support vector machine. In order to optimize the hyper-parameters of the constructed wavelet LS-SVM regression, the imperialist competition algorithm was then applied. In this study, the assessment of prediction performance is based on the squared correlation coefficient and mean absolute percentage error methods. According to the proposed method, this novel procedure was applied to a simulated case and the experimental results show that the dissolved gas contents could be accurately predicted using this method. Besides, the proposed approach was compared to other prediction methods such as the back propagation neural network, the radial basis function neural network, and generalized regression neural network. By comparison, it was inferred that this method is more effective than previous forecasting methods. Full article
(This article belongs to the Special Issue Polymers for Energy Applications)
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Open AccessArticle
The Investigation of the Seebeck Effect of the Poly(3,4-Ethylenedioxythiophene)-Tosylate with the Various Concentrations of an Oxidant
Polymers 2019, 11(1), 21; https://doi.org/10.3390/polym11010021
Received: 15 November 2018 / Revised: 20 December 2018 / Accepted: 20 December 2018 / Published: 24 December 2018
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Abstract
Poly(3,4-ethylenedioxythiophene)-tosylate (PEDOT-Tos) can be synthesized through an in situ polymerization and doping process with iron(III) p-toluenesulfonate hexahydrate as an oxidant. Both the Seebeck coefficient and the electrical conductivity were modified by varying the concentration of the oxidant. We investigated the effects of varying [...] Read more.
Poly(3,4-ethylenedioxythiophene)-tosylate (PEDOT-Tos) can be synthesized through an in situ polymerization and doping process with iron(III) p-toluenesulfonate hexahydrate as an oxidant. Both the Seebeck coefficient and the electrical conductivity were modified by varying the concentration of the oxidant. We investigated the effects of varying the concentration of the oxidant on the particle sizes and doping (oxidation) levels of PEDOT-Tos for thermoelectric applications. We demonstrated that an increase in the oxidant enabled an expansion of the particle sizes and the doping levels of the PEDOT-Tos. The modification of the doping levels by the concentration of the oxidant can provide another approach for having an optimal power factor for thermoelectric applications. De-doping of PEDOTs by reduction agents has been generally investigated for changing its oxidation levels. In this study, we investigated the effect of the concentration of the oxidant of PEDOT-Tos on the oxidation levels, the electrical conductivities and the Seebeck coefficients. As loading the oxidant of PEDOT-Tos, the Seebeck coefficient was compromised, while the electrical conductivity increased. Full article
(This article belongs to the Special Issue Polymers for Energy Applications)
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Open AccessArticle
Electrospun Enzymatic Hydrolysis Lignin-Based Carbon Nanofibers as Binder-Free Supercapacitor Electrodes with High Performance
Polymers 2018, 10(12), 1306; https://doi.org/10.3390/polym10121306
Received: 10 October 2018 / Revised: 11 November 2018 / Accepted: 13 November 2018 / Published: 26 November 2018
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Abstract
Carbon nanofibers consisting of Poly(acrylonitrile) (PAN) and enzymatic hydrolysis lignin (EHL) were prepared in the present study by electrospinning followed by stabilization in air and carbonization in N2 environment. The morphology and structure of the electrospun carbon nanofibers were characterized by Scanning [...] Read more.
Carbon nanofibers consisting of Poly(acrylonitrile) (PAN) and enzymatic hydrolysis lignin (EHL) were prepared in the present study by electrospinning followed by stabilization in air and carbonization in N2 environment. The morphology and structure of the electrospun carbon nanofibers were characterized by Scanning Electron Microscopy (SEM), Brunauer-Emmett-Teller (BET), Roman, and the electrochemical performances were then evaluated by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS)methods. When the amount of EHL was 60 wt. %, the as-prepared nanofibers have the smallest average diameter of 172 nm and the largest BET specific surface area of 675 m2/g without activating treatment. The carbon nanofiber electrode showed excellent specific capacitance of 216.8 F/g at the current density of 1 A/g, maintaining 88.8% capacitance retention after 2000 cycles. Moreover, the carbon nanofiber electrode containing 60 wt. % exhibited a smaller time constant (0.5 s) in comparison to that of carbon nanofibers in literatures. These findings suggest the potential use of EHL could be a practical as a sustainable alternative for PAN in carbon electrode manufacturing. Full article
(This article belongs to the Special Issue Polymers for Energy Applications)
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Open AccessArticle
Facile NiOx Sol-Gel Synthesis Depending on Chain Length of Various Solvents without Catalyst for Efficient Hole Charge Transfer in Perovskite Solar Cells
Polymers 2018, 10(11), 1227; https://doi.org/10.3390/polym10111227
Received: 30 September 2018 / Revised: 1 November 2018 / Accepted: 1 November 2018 / Published: 6 November 2018
Cited by 1 | PDF Full-text (2687 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Nickel oxide (NiOx)–based perovskite solar cells (PSCs) have recently gained considerable interest, and exhibit above 20% photovoltaic efficiency. However, the reported syntheses of NiOx sol-gel used toxic chemicals for the catalysts during synthesis, which resulted in a high-temperature annealing requirement [...] Read more.
Nickel oxide (NiOx)–based perovskite solar cells (PSCs) have recently gained considerable interest, and exhibit above 20% photovoltaic efficiency. However, the reported syntheses of NiOx sol-gel used toxic chemicals for the catalysts during synthesis, which resulted in a high-temperature annealing requirement to remove the organic catalysts (ligands). Herein, we report a facile “NiOx sol-gel depending on the chain length of various solvents” method that eschews toxic catalysts, to confirm the effect of different types of organic solvents on NiOx synthesis. The optimized conditions of the method resulted in better morphology and an increase in the crystallinity of the perovskite layer. Furthermore, the use of the optimized organic solvent improved the absorbance of the photoactive layer in the PSC device. To compare the electrical properties, a PSC was prepared with a p-i-n structure, and the optimized divalent alcohol-based NiOx as the hole transport layer. This improved the charge transport compared with that for the typical 1,2-ethanediol (ethylene glycol) used in earlier studies. Finally, the optimized solvent-based NiOx enhanced device performance by increasing the short-circuit current density (Jsc), open-circuit voltage (Voc), and fill factor (FF), compared with those of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)–based devices. Full article
(This article belongs to the Special Issue Polymers for Energy Applications)
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Open AccessArticle
Recycled Carbon Fiber-Supported Polyaniline/Manganese Dioxide Prepared via One-Step Electrodeposition for Flexible Supercapacitor Integrated Electrodes
Polymers 2018, 10(10), 1152; https://doi.org/10.3390/polym10101152
Received: 12 September 2018 / Revised: 11 October 2018 / Accepted: 12 October 2018 / Published: 16 October 2018
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Abstract
The exploration of multifunctional electrode materials has been a hotspot for the development of high-performance supercapacitors. We have used carbon fiber plates recovered from construction waste to prepare high-quality flexible carbon fiber materials by pyrolysis of epoxy resin. The as-prepared recycled carbon fiber [...] Read more.
The exploration of multifunctional electrode materials has been a hotspot for the development of high-performance supercapacitors. We have used carbon fiber plates recovered from construction waste to prepare high-quality flexible carbon fiber materials by pyrolysis of epoxy resin. The as-prepared recycled carbon fiber has a diameter of 8 μm and is the perfect substrate material for flexible electrode materials. Furthermore, polyaniline and manganese dioxide are uniformly deposited on the recycled carbon fiber by one-step electrodeposition to form an active film. The recycled carbon fiber/polyaniline/MnO2 composite shows an excellent specific capacitance of 475.1 F·g−1 and capacitance retention of 86.1% after 5000 GCD cycles at 1 A·g−1 in 1 M Na2SO4 electrolyte. The composites optimized for electrodeposition time have more electroactive sites, faster ions and electron transfer, structural stability and higher conductivity, endowing the composites promising application prospect. Full article
(This article belongs to the Special Issue Polymers for Energy Applications)
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Open AccessArticle
A Novel Fault Diagnosis System on Polymer Insulation of Power Transformers Based on 3-stage GA–SA–SVM OFC Selection and ABC–SVM Classifier
Polymers 2018, 10(10), 1096; https://doi.org/10.3390/polym10101096
Received: 24 September 2018 / Revised: 1 October 2018 / Accepted: 1 October 2018 / Published: 3 October 2018
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Abstract
Dissolved gas analysis (DGA) has been widely used in various scenarios of power transformers’ online monitoring and diagnoses. However, the diagnostic accuracy of traditional DGA methods still leaves much room for improvement. In this context, numerous new DGA diagnostic models that combine artificial [...] Read more.
Dissolved gas analysis (DGA) has been widely used in various scenarios of power transformers’ online monitoring and diagnoses. However, the diagnostic accuracy of traditional DGA methods still leaves much room for improvement. In this context, numerous new DGA diagnostic models that combine artificial intelligence with traditional methods have emerged. In this paper, a new DGA artificial intelligent diagnostic system is proposed. There are two modules that make up the diagnosis system. The two modules are the optimal feature combination (OFC) selection module based on 3-stage GA–SA–SVM and the ABC–SVM fault diagnosis module. The diagnosis system has been completely realized and embodied in its outstanding performances in diagnostic accuracy, reliability, and efficiency. Comparing the result with other artificial intelligence diagnostic methods, the new diagnostic system proposed in this paper performed superiorly. Full article
(This article belongs to the Special Issue Polymers for Energy Applications)
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Open AccessArticle
Polyaniline/Carbon Nanotubes Composite Modified Anode via Graft Polymerization and Self-Assembling for Microbial Fuel Cells
Polymers 2018, 10(7), 759; https://doi.org/10.3390/polym10070759
Received: 30 June 2018 / Revised: 30 June 2018 / Accepted: 3 July 2018 / Published: 10 July 2018
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Abstract
Microbial fuel cells (MFCs) are promising devices for sustainable energy production, wastewater treatment and biosensors. Anode materials directly interact with electricigens and accept electrons between cells, playing an important role in determining the performance of MFCs. In this study, a novel carbon nanotubes [...] Read more.
Microbial fuel cells (MFCs) are promising devices for sustainable energy production, wastewater treatment and biosensors. Anode materials directly interact with electricigens and accept electrons between cells, playing an important role in determining the performance of MFCs. In this study, a novel carbon nanotubes (CNTs) and polyaniline (PANI) nanocomposite film modified Indium-tin oxide (ITO) anode was fabricated through graft polymerization of PANI after the modification of γ-aminopropyltriethoxysilane (APTES) on ITO substrate, which was followed by layer-by-layer (LBL) self-assembling of CNTs and PANI alternatively on its surface. (CNTs/PANI)n/APTES/ITO electrode with low charge transfer resistance showed better electrochemical behavior compared to the bare ITO electrode. Twelve layers of CNTs/PANI decorated ITO electrode with an optimal nanoporous network exhibited superior biocatalytic properties with a maximal current density of 6.98 µA/cm2, which is 26-fold higher than that of conventional ITO electrode in Shewanella loihica PV-4 bioelectrochemical system. MFCs with (CNTs/PANI)12/APTES/ITO as the anode harvested a maximum output power density of 34.51 mW/m2, which is 7.5-fold higher than that of the unmodified ITO electrode. These results demonstrate that (CNTs/PANI)12/APTES/ITO electrode has superior electrochemical and electrocatalytic properties compared to the bare ITO electrode, while the cellular toxicity of CNTs has an effect on the performance of MFC with (CNTs/PANI)n/APTES/ITO electrode. Full article
(This article belongs to the Special Issue Polymers for Energy Applications)
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Open AccessArticle
Enhanced Performance of Inverted Non-Fullerene Organic Solar Cells by Using Metal Oxide Electron- and Hole-Selective Layers with Process Temperature ≤150 °C
Polymers 2018, 10(7), 725; https://doi.org/10.3390/polym10070725
Received: 12 May 2018 / Revised: 30 May 2018 / Accepted: 31 May 2018 / Published: 2 July 2018
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Abstract
In this work, an efficient inverted organic solar cell (OSC) based on the non-fullerene PBDB-T:IT-M blend system is demonstrated by using an aqueous solution processed ZnO electron-selective layer with the whole process temperature ≤150 °C and a thermally evaporated MoO3 hole-selective layer [...] Read more.
In this work, an efficient inverted organic solar cell (OSC) based on the non-fullerene PBDB-T:IT-M blend system is demonstrated by using an aqueous solution processed ZnO electron-selective layer with the whole process temperature ≤150 °C and a thermally evaporated MoO3 hole-selective layer The ZnO selective layer is deposited by aqueous solution and prepared in a low-temperature process, so that it can be compatible with the roll-to-roll process. The proposed device achieves an enhanced power conversion efficiency (PCE) of 9.33% compared with the device based on the high-temperature sol-gel-processed ZnO selective layer, which achieves a PCE of 8.62%. The inverted device also shows good stability, keeping more than 82% of its initial PCE after being stored under ambient air conditions and a humidity of around 40% without any encapsulation for 240 h. The results show the potential for the fabrication of efficient non-fullerene OSCs with low-temperature metal oxide selective layers. Full article
(This article belongs to the Special Issue Polymers for Energy Applications)
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Open AccessArticle
36% Enhanced Efficiency of Ternary Organic Solar Cells by Doping a NT-Based Polymer as an Electron-Cascade Donor
Polymers 2018, 10(7), 703; https://doi.org/10.3390/polym10070703
Received: 25 May 2018 / Revised: 14 June 2018 / Accepted: 14 June 2018 / Published: 25 June 2018
Cited by 2 | PDF Full-text (2430 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
In recent years, ternary organic photovoltaic cells (OPVs) have been dedicated to improving power conversion efficiency (PCE) by broadening optical absorption spectra. Ternary OPVs with different poly[thieno[3,2-b]thiophene-2,5-diyl-alt-4,9-bis(4-(2-decyltetradecyl)thien-2-yl)naphtho[1,2-c:5,6-c’]bis[1,2,5]thiadiazole-5,5′-diyl] (PTT-DTNT-DT) doping concentrations were designed and the effect of PTT-DTNT-DT as a complementary electron donor on [...] Read more.
In recent years, ternary organic photovoltaic cells (OPVs) have been dedicated to improving power conversion efficiency (PCE) by broadening optical absorption spectra. Ternary OPVs with different poly[thieno[3,2-b]thiophene-2,5-diyl-alt-4,9-bis(4-(2-decyltetradecyl)thien-2-yl)naphtho[1,2-c:5,6-c’]bis[1,2,5]thiadiazole-5,5′-diyl] (PTT-DTNT-DT) doping concentrations were designed and the effect of PTT-DTNT-DT as a complementary electron donor on the performance of OPVs was investigated. The optimized PCE of OPVs was increased from 3.42% to 4.66% by doping 20 wt % PTT-DTNT-DT. The remarkable improvement in the performance of the ternary device is mainly attributed to the sharp increase in the short-circuit current density and fill-factor. The major reasons have been systematically studied from atomic force microscopy, electrochemical impedance spectroscopy, surface energy, space charge limited current and photocurrent behavior. It has been found that the separation of excitons and the transportation of charge are enhanced while light absorption is increased, and the charge recombination also decreases due to the optimization of the cascade energy level and the morphology of the ternary active layer. The results show that it is feasible to improve the performance of ternary OPVs by their complementary absorption. Full article
(This article belongs to the Special Issue Polymers for Energy Applications)
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Open AccessArticle
Appropriate Donor-Acceptor Phase Separation Structure for the Enhancement of Charge Generation and Transport in Polymer Solar Cells
Polymers 2018, 10(3), 332; https://doi.org/10.3390/polym10030332
Received: 15 February 2018 / Revised: 13 March 2018 / Accepted: 16 March 2018 / Published: 18 March 2018
Cited by 1 | PDF Full-text (2841 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The morphology of active layer for polymer solar cells is critical to enhance the performance especially for fill factor of the devices. To investigate the relationship between active layer morphology and performance of polymer solar cells (PSCs), 1,8-diiodooctane (DIO) additive, and [6,6]-phenyl-C71 [...] Read more.
The morphology of active layer for polymer solar cells is critical to enhance the performance especially for fill factor of the devices. To investigate the relationship between active layer morphology and performance of polymer solar cells (PSCs), 1,8-diiodooctane (DIO) additive, and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) electron acceptor were used to regulate the aggregation morphology of copolymer poly(thieno[3,4-b]-thiophene/benzodithiophene) (PTB7) electron donor from solution state to solid state. Atom force microscopy (AFM), steady-state absorption (UV-Vis), time-resolved absorption (TA), spectroelectrochemistry (SEC) and current-voltage (J-V) measurements were employed to characterize the morphology, optical and electrical characteristics of active layers and to reveal the relationship among the morphology, photophysical property, and performance of PTB7-based devices. The results show that DIO can refine the aggregation scale of PTB7 during the dissolution process, whereas both the aggregation scale and aggregation behaviors of PTB7 donor are affected by PC71BM acceptor molecules. Furthermore, the bulk heterojunction structure (BHJ) morphology of active layer can be optimized during the DIO evaporation process. TA kinetic data indicate that the population and lifetime of charged species are improved in the DIO-treated BHJ active layer. Moreover, the active layers with DIO treatment have a relative low highest occupied molecular orbital (HOMO) energy level, which makes hole transport more easily in PTB7 donor phase. As a result, the performance of PTB7-based PSCs is enhanced. Full article
(This article belongs to the Special Issue Polymers for Energy Applications)
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Open AccessArticle
Comparative Investigation on the Performance of Modified System Poles and Traditional System Poles Obtained from PDC Data for Diagnosing the Ageing Condition of Transformer Polymer Insulation Materials
Polymers 2018, 10(2), 191; https://doi.org/10.3390/polym10020191
Received: 8 January 2018 / Revised: 31 January 2018 / Accepted: 12 February 2018 / Published: 14 February 2018
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Abstract
The life expectancy of a transformer is largely depended on the service life of transformer polymer insulation materials. Nowadays, several papers have reported that the traditional system poles obtained from polarization and depolarization current (PDC) data can be used to assess the condition [...] Read more.
The life expectancy of a transformer is largely depended on the service life of transformer polymer insulation materials. Nowadays, several papers have reported that the traditional system poles obtained from polarization and depolarization current (PDC) data can be used to assess the condition of transformer insulation systems. However, the traditional system poles technique only provides limited ageing information for transformer polymer insulation. In this paper, the modified system poles obtained from PDC data are proposed to assess the ageing condition of transformer polymer insulation. The aim of the work is to focus on reporting a comparative investigation on the performance of modified system poles and traditional system poles for assessing the ageing condition of a transformer polymer insulation system. In the present work, a series of experiments have been performed under controlled laboratory conditions. The PDC measurement data, degree of polymerization (DP) and moisture content of the oil-immersed polymer pressboard specimens were carefully monitored. It is observed that, compared to the relationships between traditional system poles and DP values, there are better correlations between the modified system poles and DP values, because the modified system poles can obtain much more ageing information on transformer polymer insulation. Therefore, the modified system poles proposed in the paper are more suitable for the diagnosis of the ageing condition of transformer polymer insulation. Full article
(This article belongs to the Special Issue Polymers for Energy Applications)
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Open AccessArticle
Improving Photovoltaic Properties of P3HT:IC60BA through the Incorporation of Small Molecules
Polymers 2018, 10(2), 121; https://doi.org/10.3390/polym10020121
Received: 8 January 2018 / Revised: 22 January 2018 / Accepted: 24 January 2018 / Published: 26 January 2018
Cited by 6 | PDF Full-text (3060 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
We investigated the role of a functional solid additive, 2,3-dihydroxypyridine (DHP), in influencing the optoelectronic, morphological, structural and photovoltaic properties of bulk-heterojunction-based polymer solar cells (BHJ PSCs) fabricated using poly(3-hexylthiophene): indene-C60 bisadduct (P3HT:IC60BA) photoactive medium. A dramatic increase in the [...] Read more.
We investigated the role of a functional solid additive, 2,3-dihydroxypyridine (DHP), in influencing the optoelectronic, morphological, structural and photovoltaic properties of bulk-heterojunction-based polymer solar cells (BHJ PSCs) fabricated using poly(3-hexylthiophene): indene-C60 bisadduct (P3HT:IC60BA) photoactive medium. A dramatic increase in the power conversion efficiency (~20%) was witnessed for the BHJ PSCs treated with DHP compared to the pristine devices. A plausible explanation describing the alignment of pyridine moieties of DHP with the indene side groups of IC60BA is presented with a view to improving the performance of the BHJ PSCs via improved crystalline order and hydrophobicity changes. Full article
(This article belongs to the Special Issue Polymers for Energy Applications)
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Review

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Open AccessReview
Polymeric Materials for Conversion of Electromagnetic Waves from the Sun to Electric Power
Polymers 2018, 10(3), 307; https://doi.org/10.3390/polym10030307
Received: 10 February 2018 / Revised: 2 March 2018 / Accepted: 6 March 2018 / Published: 12 March 2018
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Abstract
Solar photoelectric energy converted into electricity requires large surface areas with incident light and flexible materials to capture these light emissions. Currently, sunlight rays are converted to electrical energy using silicon polymeric material with efficiency up to 22%. The majority of the energy [...] Read more.
Solar photoelectric energy converted into electricity requires large surface areas with incident light and flexible materials to capture these light emissions. Currently, sunlight rays are converted to electrical energy using silicon polymeric material with efficiency up to 22%. The majority of the energy is lost during conversion due to an energy gap between sunlight photons and polymer energy transformation. This energy conversion also depends on the morphology of present polymeric materials. Therefore, it is very important to construct mechanisms of highest energy occupied molecular orbitals (HOMO)s and the lowest energy unoccupied molecular orbitals (LUMO)s to increase the efficiency of conversion. The organic and inorganic solar cells used as dyes can absorb more photons from sunlight and the energy gap will be less for better conversion of energy to electricity than the conventional solar cells. This paper provides an up-to-date review on the performance, characterization, and reliability of different composite polymeric materials for energy conversion. Specific attention has been given to organic solar cells because of their several advantages over others, such as their low-energy payback time, conversion efficiency and greenhouse emissions. Finally, this paper provides the recent progress on the application of both organic and inorganic solar cells for electric power generations together with several challenges that are currently faced. Full article
(This article belongs to the Special Issue Polymers for Energy Applications)
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