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Application of Polymers in (Photo)electrochemical Devices: From Solar Cells to Batteries

A special issue of Polymers (ISSN 2073-4360). This special issue belongs to the section "Polymer Applications".

Deadline for manuscript submissions: closed (20 March 2022) | Viewed by 77175

Special Issue Editors


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Guest Editor
Department of Chemistry, University of Turin, 10125 Turin, Italy
Interests: photovoltaic; dye-sensitized solar cells; perovskite solar cells; deep eutectic solvents; ionic liquids
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Co-Guest Editor
Group for Applied Materials and Electrochemistry – GAMELab, Department of Applied Science and Technology, Polytechnic University of Turin, 10129 Turin, Italy
Interests: lithium-based and post-lithium batteries; polymer electrolytes; nanostructured electrodes; sustainable polymers and processes
Special Issues, Collections and Topics in MDPI journals

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Co-Guest Editor
Department Electronic Engineering, University of Rome Tor Vergata, Rome, Italy
Interests: optoelectronics; organic polymers; PSC; OPV

Special Issue Information

Dear Colleagues,

In the last several decades, both organic and inorganic polymers have been intensively studied as active/inactive materials in different application fields, ranging from coatings to biomimetics to electronics and energy conversion/storage. In particular, the use of polymers, which can be easily tailored as desired, as electrolytes in batteries, and in organic and perovskite solar cells as active or charge transport layers, has allowed unprecedented breakthroughs.

This Special Issue aims at collecting the recent advances in the application of functional polymeric materials in electrochemical energy storage/conversion, as well as electronic and optoelectronic devices. Additionally, contributions on smart and sustainable synthetic approaches toward green functional polymers are warmly welcomed.

Dr. Matteo Bonomo
Prof. Dr. Claudio Gerbaldi
Prof. Dr. Francesca Brunetti
Guest Editors

Manuscript Submission Information

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Keywords

  • polymers
  • solar cells
  • batteries
  • fuel cells
  • electrolytes
  • perovskite solar cells
  • organic photovoltaics

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Published Papers (12 papers)

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Research

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11 pages, 3789 KiB  
Article
Graphene with Ni-Grid as Semitransparent Electrode for Bulk Heterojunction Solar Cells (BHJ-SCs)
by Martina Dianetti, Gianpaolo Susanna, Emanuele Calabrò, Giuseppina Polino, Martin Otto, Daniel Neumaier, Andrea Reale and Francesca Brunetti
Polymers 2022, 14(5), 1046; https://doi.org/10.3390/polym14051046 - 5 Mar 2022
Cited by 3 | Viewed by 2278
Abstract
In this work, we present the fabrication and characterization of bulk-heterojunction solar cells on monolayer graphene (MLG) with nickel-grids (Ni-grid) as semitransparent conductive electrode. The electrodes showed a maximum transmittance of 90% (calculated in 300–800 nm range) and a sheet resistance down to [...] Read more.
In this work, we present the fabrication and characterization of bulk-heterojunction solar cells on monolayer graphene (MLG) with nickel-grids (Ni-grid) as semitransparent conductive electrode. The electrodes showed a maximum transmittance of 90% (calculated in 300–800 nm range) and a sheet resistance down to 35 Ω/□. On these new anodes, we fabricated TCO free BHJ-SCs using PTB7 blended with PC70BM fullerene derivative as active layer. The best device exhibited a power conversion efficiency (PCE) of 4.2% in direct configuration and 3.6% in inverted configuration. The reference solar cell, realized on the ITO glass substrate, achieved a PCE of 6.1% and 6.7% in direct and inverted configuration respectively; for comparison we also tested OSCs only with simple Ni-grid as semitransparent and conductive electrode, obtaining a low PCE of 0.7%. The proposed approach to realize graphene-based electrodes could be a possible route to reduce the overall impact of the sheet resistance of this type of electrodes allowing their use in several optoelectronic devices. Full article
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20 pages, 5425 KiB  
Article
Conception and Theoretical Study of a New Copolymer Based on MEH-PPV and P3HT: Enhancement of the Optoelectronic Properties for Organic Photovoltaic Cells
by Mariem Ltayef, Maha M. Almoneef, Walid Taouali, Mohamed Mbarek and Kamel Alimi
Polymers 2022, 14(3), 513; https://doi.org/10.3390/polym14030513 - 27 Jan 2022
Cited by 9 | Viewed by 3135
Abstract
A new copolymer has been studied, which is formed by Poly(2-methoxy-5-(2-ethyl-hexyloxy)-1,4-phenylene-vinylene) (MEH-PPV) and poly(3-hexylthiophene) (P3HT). The choice of these π-conjugated polymers was based on their semiconductor characters and their great applicability in electronic organic devices. The structure and vibrational and optoelectronic properties were [...] Read more.
A new copolymer has been studied, which is formed by Poly(2-methoxy-5-(2-ethyl-hexyloxy)-1,4-phenylene-vinylene) (MEH-PPV) and poly(3-hexylthiophene) (P3HT). The choice of these π-conjugated polymers was based on their semiconductor characters and their great applicability in electronic organic devices. The structure and vibrational and optoelectronic properties were simulated by calculations based on DFT, TD-DFT, and ZINDO. This material shows original and unique properties compared to the basic homopolymers. Thus, the obtained results reveal that this copolymer can be mixed with the (6,6)-phenyl C61 butyric acid methyl ester (PCBM) to give existence to a new composite that can be used as an active layer for an organic solar cell. Full article
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10 pages, 1835 KiB  
Article
Charge Storage and Solar Rechargeable Battery Devices Based on Electrodes Electrochemically Modified with Conducting Polymer Nanowires
by Andrés Mauricio Ramírez, Manuel Alejandro Gacitúa, Fernando Raúl Díaz and María Angélica del Valle
Polymers 2021, 13(24), 4375; https://doi.org/10.3390/polym13244375 - 14 Dec 2021
Cited by 2 | Viewed by 2212
Abstract
In this work, the use of nanostructured conducting polymer deposits on energy-storing devices is described. The cathode and the anode are electrochemically modified with nanowires of polypyrrole and poly(3,4-ethylenedioxythiophene), respectively, prepared after the use of a mesoporous silica template. The effect of aqueous [...] Read more.
In this work, the use of nanostructured conducting polymer deposits on energy-storing devices is described. The cathode and the anode are electrochemically modified with nanowires of polypyrrole and poly(3,4-ethylenedioxythiophene), respectively, prepared after the use of a mesoporous silica template. The effect of aqueous or ionic liquid medium is assayed during battery characterization studies. The nanostructured device greatly surpasses the performance of the bulk configuration in terms of specific capacity, energy, and power. Moreover, compared with devices found in the literature with similar designs, the nanostructured device prepared here shows better battery characteristics, including cyclability. Finally, considering the semi-conducting properties of the components, the device was adapted to the design of a solar-rechargeable device by the inclusion of a titanium oxide layer and cis-bis(isothiocyanate)-bis(2,2′-bipyridyl-4,4′-dicarboxylate) ruthenium (II) dye. The device proved that the nanostructured design is also appropriate for the implementation of solar-rechargeable battery, although its performance still requires further optimization. Full article
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13 pages, 2338 KiB  
Article
Effect of Thermal Stabilization on PAN-Derived Electrospun Carbon Nanofibers for CO2 Capture
by Elisa Maruccia, Stefania Ferrari, Mattia Bartoli, Lorenzo Lucherini, Giuseppina Meligrana, Candido F. Pirri, Guido Saracco and Claudio Gerbaldi
Polymers 2021, 13(23), 4197; https://doi.org/10.3390/polym13234197 - 30 Nov 2021
Cited by 5 | Viewed by 2714
Abstract
Carbon capture is amongst the key emerging technologies for the mitigation of greenhouse gases (GHG) pollution. Several materials as adsorbents for CO2 and other gases are being developed, which often involve using complex and expensive fabrication techniques. In this work, we suggest [...] Read more.
Carbon capture is amongst the key emerging technologies for the mitigation of greenhouse gases (GHG) pollution. Several materials as adsorbents for CO2 and other gases are being developed, which often involve using complex and expensive fabrication techniques. In this work, we suggest a sound, easy and cheap route for the production of nitrogen-doped carbon materials for CO2 capture by pyrolysis of electrospun poly(acrylonitrile) (PAN) fibers. PAN fibers are generally processed following specific heat treatments involving up to three steps (to get complete graphitization), one of these being stabilization, during which PAN fibers are oxidized and stretched in the 200–300 °C temperature range. The effect of stabilization temperature on the chemical structure of the carbon nanofibers is investigated herein to ascertain the possible implication of incomplete conversion/condensation of nitrile groups to form pyridine moieties on the CO2 adsorption capacity. The materials were tested in the pure CO2 atmosphere at 20 °C achieving 18.3% of maximum weight increase (equivalent to an uptake of 4.16 mmol g−1), proving the effectiveness of a high stabilization temperature as route for the improvement of CO2 uptake. Full article
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14 pages, 2993 KiB  
Article
Electrochemically Obtained Polysulfonates Doped Poly(3,4-ethylenedioxythiophene) Films—Effects of the Dopant’s Chain Flexibility and Molecular Weight Studied by Electrochemical, Microgravimetric and XPS Methods
by Vladimir Lyutov, Varvara Kabanova, Oxana Gribkova, Alexander Nekrasov and Vessela Tsakova
Polymers 2021, 13(15), 2438; https://doi.org/10.3390/polym13152438 - 24 Jul 2021
Cited by 4 | Viewed by 2215
Abstract
Electrochemically synthesized poly(3,4,-ethylenedioxythiophene) (PEDOT) films obtained in the presence of eight different polysulfonate dopants are comparatively studied by means of electrochemical quartz crystal microbalance (EQCM) and X-ray Photoelectron Spectroscopy (XPS). Differences with respect to oxidation and doping levels (OL and DL), polymerization efficiency [...] Read more.
Electrochemically synthesized poly(3,4,-ethylenedioxythiophene) (PEDOT) films obtained in the presence of eight different polysulfonate dopants are comparatively studied by means of electrochemical quartz crystal microbalance (EQCM) and X-ray Photoelectron Spectroscopy (XPS). Differences with respect to oxidation and doping levels (OL and DL), polymerization efficiency and redox behavior are revealed based on the interplay of three factors: the type of the dopant (acid or salt form), flexibility of the polysulfonate chains and molecular weight of the polysulfonate species. For the rigid- and semi-rigid-chain dopants, use of the salt form results in higher OL and DL values and substantial involvement of solvent molecules in the course of polymerization and redox transitions whereas in the presence of their acid form compact PEDOT films with minor ionic-solvent fluxes upon redox transitions are formed. In contrast, use of the salt form of the flexible chain polysulfonates results in PEDOT with lower OL and DL in comparison to the corresponding acid form. Significant effects are observed when comparing flexible chain dopants with different molecular weights. From a practical point of view the present investigations demonstrate the large scope of possibilities to influence some basic properties of PEDOT (Ol and DL, intensity and type of the ionic and solvent fluxes upon redox transition) depending on the used polysulfonate dopants. Full article
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15 pages, 3887 KiB  
Article
Optimization of Sb2S3 Nanocrystal Concentrations in P3HT: PCBM Layers to Improve the Performance of Polymer Solar Cells
by E. M. Mkawi, Y. Al-Hadeethi, R. S. Bazuhair, A. S. Yousef, E. Shalaan, B. Arkook, A. M. Abdeldaiem, Rahma Almalki and E. Bekyarova
Polymers 2021, 13(13), 2152; https://doi.org/10.3390/polym13132152 - 29 Jun 2021
Cited by 10 | Viewed by 3418
Abstract
In this study, polymer solar cells were synthesized by adding Sb2S3 nanocrystals (NCs) to thin blended films with polymer poly(3-hexylthiophene)(P3HT) and [6,6]-phenyl-C61-butyric-acid-methyl-ester (PCBM) as the p-type material prepared via the spin-coating method. The purpose of this study is [...] Read more.
In this study, polymer solar cells were synthesized by adding Sb2S3 nanocrystals (NCs) to thin blended films with polymer poly(3-hexylthiophene)(P3HT) and [6,6]-phenyl-C61-butyric-acid-methyl-ester (PCBM) as the p-type material prepared via the spin-coating method. The purpose of this study is to investigate the dependence of polymer solar cells’ performance on the concentration of Sb2S3 nanocrystals. The effect of the Sb2S3 nanocrystal concentrations (0.01, 0.02, 0.03, and 0.04 mg/mL) in the polymer’s active layer was determined using different characterization techniques. X-ray diffraction (XRD) displayed doped ratio dependences of P3HT crystallite orientations of P3HT crystallites inside a block polymer film. Introducing Sb2S3 NCs increased the light harvesting and regulated the energy levels, improving the electronic parameters. Considerable photoluminescence quenching was observed due to additional excited electron pathways through the Sb2S3 NCs. A UV–visible absorption spectra measurement showed the relationship between the optoelectronic properties and improved surface morphology, and this enhancement was detected by a red shift in the absorption spectrum. The absorber layer’s doping concentration played a definitive role in improving the device’s performance. Using a 0.04 mg/mL doping concentration, a solar cell device with a glass /ITO/PEDOT:PSS/P3HT-PCBM: Sb2S3:NC/MoO3/Ag structure achieved a maximum power conversion efficiency of 2.72%. These Sb2S3 NCs obtained by solvothermal fabrication blended with a P3HT: PCBM polymer, would pave the way for a more effective design of organic photovoltaic devices. Full article
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13 pages, 3077 KiB  
Article
Addressing Manufacturability and Processability in Polymer Gel Electrolytes for Li/Na Batteries
by Víctor Gregorio, Nuria García and Pilar Tiemblo
Polymers 2021, 13(13), 2093; https://doi.org/10.3390/polym13132093 - 24 Jun 2021
Cited by 3 | Viewed by 2275
Abstract
Gel electrolytes are prepared with Ultra High Molecular Weight (UHMW) polyethylene oxide (PEO) in a concentration ranging from 5 to 30 wt.% and Li- and Na-doped 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (PYR14-TFSI) by a simple procedure consisting of dissolving PEO by melting it directly in the [...] Read more.
Gel electrolytes are prepared with Ultra High Molecular Weight (UHMW) polyethylene oxide (PEO) in a concentration ranging from 5 to 30 wt.% and Li- and Na-doped 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (PYR14-TFSI) by a simple procedure consisting of dissolving PEO by melting it directly in the liquid electrolyte while stirring the blend. This procedure is fast, reproducible and needs no auxiliary solvents, which makes it sustainable and potentially easy to scale up for mass production. The viability of the up-scaling by extrusion has been studied. Extrusion has been chosen because it is a processing method commonly employed in the plastics industry. The structure and morphology of the gel electrolytes prepared by both methods have been studied by DSC and FTIR, showing small differences among the two methods. Composite gels incorporation high concentrations of surface modified sepiolite fibers have been successfully prepared by extrusion. The rheological behavior and ionic conductivity of the gels have been characterized, and very similar performance of the extruded and manually mixed gels is detected. Ionic conductivity of all the gels, including the composites, are at or over 0.4 mS cm−1 at 25 °C, being at the same time thermoreversible and self-healing gels, tough, sticky, transparent and stretchable. This combination of properties, together with the viability of their industrial up-scaling, makes these gel electrolyte families very attractive for their application in energy storage devices. Full article
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15 pages, 4390 KiB  
Article
Macromolecular Engineering of Poly(catechol) Cathodes towards High-Performance Aqueous Zinc-Polymer Batteries
by Nagaraj Patil, Jesus Palma and Rebeca Marcilla
Polymers 2021, 13(11), 1673; https://doi.org/10.3390/polym13111673 - 21 May 2021
Cited by 13 | Viewed by 3355
Abstract
Aqueous zinc-polymer batteries (AZPBs) comprising abundant Zn metal anode and redox-active polymer (RAP) cathodes can be a promising solution for accomplishing viable, safe and sustainable energy storage systems. Though a limited number of RAPs have been successfully applied as organic cathodes in AZPBs, [...] Read more.
Aqueous zinc-polymer batteries (AZPBs) comprising abundant Zn metal anode and redox-active polymer (RAP) cathodes can be a promising solution for accomplishing viable, safe and sustainable energy storage systems. Though a limited number of RAPs have been successfully applied as organic cathodes in AZPBs, their macromolecular engineering towards improving electrochemical performance is rarely considered. In this study, we systematically compare performance of AZPB comprising Zn metal anode and either poly(catechol) homopolymer (named P(4VC)) or poly(catechol) copolymer (named P(4VC86-stat-SS14)) as polymer cathodes. Sulfonate anionic pendants in copolymer not only rendered lower activation energy and higher rate constant, but also conferred lower charge-transfer resistance, as well as facilitated Zn2+ mobility and less diffusion-controlled current responses compared to its homopolymer analogue. Consequently, the Zn||P(4VC86-stat-SS14) full-cell exhibits enhanced gravimetric (180 versus 120 mAh g−1 at 30 mg cm−2) and areal capacity (5.4 versus 3.6 mAh cm−2 at 30 mg cm−2) values, as well as superior rate capability both at room temperature (149 versus 105 mAh g−1 at 150 C) and at −35 °C (101 versus 35 mAh g−1 at 30 C) compared to Zn||P(4VC)100. This overall improved performance for Zn||P(4VC86-stat-SS14) is highly encouraging from the perspective applying macromolecular engineering strategies and paves the way for the design of advanced high-performance metal-organic batteries. Full article
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17 pages, 5146 KiB  
Article
Effect of Iodine Filler on Photoisomerization Kinetics of Photo-Switchable Thin Films Based on PEO-BDK-MR
by Qais M. Al-Bataineh, A. A. Ahmad, A. M. Alsaad, I. A. Qattan, Ihsan A. Aljarrah and Ahmad D. Telfah
Polymers 2021, 13(5), 841; https://doi.org/10.3390/polym13050841 - 9 Mar 2021
Cited by 1 | Viewed by 2476
Abstract
We report the effect of an iodine filler on photoisomerization kinetics of photo-switchable PEO-BDK-MR thin films. The kinetics of photoisomerization and time progression of PEO-BDK-MR/I2 nanocomposite thin films are investigated using UV-Vis, FTIR spectroscopies, and modified mathematical models developed using new analytical [...] Read more.
We report the effect of an iodine filler on photoisomerization kinetics of photo-switchable PEO-BDK-MR thin films. The kinetics of photoisomerization and time progression of PEO-BDK-MR/I2 nanocomposite thin films are investigated using UV-Vis, FTIR spectroscopies, and modified mathematical models developed using new analytical methods. Incorporating iodine filler into the PEO-BDK-MR polymeric matrix enhances the isomerization energy barrier and considerably increases the processing time. Our outcomes propose that enhanced photoisomerized and time processed (PEO-BDK-MR)/I2 thin films could be potential candidates for a variety of applications involving molecular solar thermal energy storage media. Full article
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19 pages, 57627 KiB  
Article
Cobalt Oxide Nanograins and Silver Nanoparticles Decorated Fibrous Polyaniline Nanocomposite as Battery-Type Electrode for High Performance Supercapattery
by Javed Iqbal, Arshid Numan, Mohammad Omaish Ansari, Rashida Jafer, Priyanka R. Jagadish, Shahid Bashir, P. M. Z. Hasan, Anwar L. Bilgrami, Sharifah Mohamad, K. Ramesh and S. Ramesh
Polymers 2020, 12(12), 2816; https://doi.org/10.3390/polym12122816 - 27 Nov 2020
Cited by 30 | Viewed by 4239
Abstract
In this study, silver (Ag) and cobalt oxide (Co3O4) decorated polyaniline (PANI) fibers were prepared by the combination of in-situ aniline oxidative polymerization and the hydrothermal methodology. The morphology of the prepared Ag/Co3O4@PANI ternary nanocomposite [...] Read more.
In this study, silver (Ag) and cobalt oxide (Co3O4) decorated polyaniline (PANI) fibers were prepared by the combination of in-situ aniline oxidative polymerization and the hydrothermal methodology. The morphology of the prepared Ag/Co3O4@PANI ternary nanocomposite was studied by scanning electron microscopy and transmission electron microscopy, while the structural studies were carried out by X-ray diffraction and X-ray photoelectron spectroscopy. The morphological characterization revealed fibrous shaped PANI, coated with Ag and Co3O4 nanograins, while the structural studies revealed high purity, good crystallinity, and slight interactions among the constituents of the Ag/Co3O4@PANI ternary nanocomposite. The electrochemical performance studies revealed the enhanced performance of the Ag/Co3O4@PANI nanocomposite due to the synergistic/additional effect of Ag, Co3O4 and PANI compared to pure PANI and Co3O4@PANI. The addition of the Ag and Co3O4 provided an extended site for faradaic reactions leading to the high specific capacity. The Ag/Co3O4@PANI ternary nanocomposite exhibited an excellent specific capacity of 262.62 C g−1 at a scan rate of 3 mV s−1. The maximum energy and power density were found to be 14.01 Wh kg−1 and 165.00 W kg−1, respectively. The cyclic stability of supercapattery (Ag/Co3O4@PANI//activated carbon) consisting of a battery type electrode demonstrated a gradual increase in specific capacity with a continuous charge–discharge cycle until ~1000 cycles, then remained stable until 2500 cycles and later started decreasing, thereby showing the cyclic stability of 121.03% of its initial value after 3500 cycles. Full article
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Review

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61 pages, 9836 KiB  
Review
Polymeric Dopant-Free Hole Transporting Materials for Perovskite Solar Cells: Structures and Concepts towards Better Performances
by Mohamed M. H. Desoky, Matteo Bonomo, Nadia Barbero, Guido Viscardi, Claudia Barolo and Pierluigi Quagliotto
Polymers 2021, 13(10), 1652; https://doi.org/10.3390/polym13101652 - 19 May 2021
Cited by 27 | Viewed by 8286
Abstract
Perovskite solar cells are a hot topic of photovoltaic research, reaching, in few years, an impressive efficiency (25.5%), but their long-term stability still needs to be addressed for industrial production. One of the most sizeable reasons for instability is the doping of the [...] Read more.
Perovskite solar cells are a hot topic of photovoltaic research, reaching, in few years, an impressive efficiency (25.5%), but their long-term stability still needs to be addressed for industrial production. One of the most sizeable reasons for instability is the doping of the Hole Transporting Material (HTM), being the salt commonly employed as a vector bringing moisture in contact with perovskite film and destroying it. With this respect, the research focused on new and stable “dopant-free” HTMs, which are inherently conductive, being able to effectively work without any addition of dopants. Notwithstanding, they show impressive efficiency and stability results. The dopant-free polymers, often made of alternated donor and acceptor cores, have properties, namely the filming ability, the molecular weight tunability, the stacking and packing peculiarities, and high hole mobility in absence of any dopant, that make them very attractive and a real innovation in the field. In this review, we tried our best to collect all the dopant-free polymeric HTMs known so far in the perovskite solar cells field, providing a brief historical introduction, followed by the classification and analysis of the polymeric structures, based on their building blocks, trying to find structure–activity relationships whenever possible. The research is still increasing and a very simple polymer (PFDT–2F–COOH) approaches PCE = 22% while some more complex ones overcome 22%, up to 22.41% (PPY2). Full article
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60 pages, 20070 KiB  
Review
Fundamental Concepts of Hydrogels: Synthesis, Properties, and Their Applications
by Shahid Bashir, Maryam Hina, Javed Iqbal, A. H. Rajpar, M. A. Mujtaba, N. A. Alghamdi, S. Wageh, K. Ramesh and S. Ramesh
Polymers 2020, 12(11), 2702; https://doi.org/10.3390/polym12112702 - 16 Nov 2020
Cited by 542 | Viewed by 38484
Abstract
In the present review, we focused on the fundamental concepts of hydrogels—classification, the polymers involved, synthesis methods, types of hydrogels, properties, and applications of the hydrogel. Hydrogels can be synthesized from natural polymers, synthetic polymers, polymerizable synthetic monomers, and a combination of natural [...] Read more.
In the present review, we focused on the fundamental concepts of hydrogels—classification, the polymers involved, synthesis methods, types of hydrogels, properties, and applications of the hydrogel. Hydrogels can be synthesized from natural polymers, synthetic polymers, polymerizable synthetic monomers, and a combination of natural and synthetic polymers. Synthesis of hydrogels involves physical, chemical, and hybrid bonding. The bonding is formed via different routes, such as solution casting, solution mixing, bulk polymerization, free radical mechanism, radiation method, and interpenetrating network formation. The synthesized hydrogels have significant properties, such as mechanical strength, biocompatibility, biodegradability, swellability, and stimuli sensitivity. These properties are substantial for electrochemical and biomedical applications. Furthermore, this review emphasizes flexible and self-healable hydrogels as electrolytes for energy storage and energy conversion applications. Insufficient adhesiveness (less interfacial interaction) between electrodes and electrolytes and mechanical strength pose serious challenges, such as delamination of the supercapacitors, batteries, and solar cells. Owing to smart and aqueous hydrogels, robust mechanical strength, adhesiveness, stretchability, strain sensitivity, and self-healability are the critical factors that can identify the reliability and robustness of the energy storage and conversion devices. These devices are highly efficient and convenient for smart, light-weight, foldable electronics and modern pollution-free transportation in the current decade. Full article
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