| 1. |
- Ajjan Godoy, Fátima Nadia
(författare)
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Biohybrid Polymer Electrodes for Renewable Energy Storage
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Daily and seasonally fluctuating energy supply and demand requires adequate energy storage solutions. In recent years electrochemical supercapacitors have attracted considerable attention due to their ability to both store and deliver electrical energy efficiently. Our efforts are focused on developing and optimizing sustainable organic electrode materials for supercapacitors based on renewable bioorganic materials, offering a cheap, environmentally friendly and scalable alternative to store energy. In particular, we are using the second most abundant biopolymer in nature, lignin (Lig), which is an insulating material. However, when used in combination with electroactive and conducting polymers such as polypyrrole (PPy) and poly(3,4-ethylenedioxythiophene) (PEDOT), the biohybrid electrodes PPy/Lig and PEDOT/Lig display significantly enhanced energy storage performance as compared to the pristine conducting polymers without the lignin. Redox cyclic voltammetry and galvanostatic charge/discharge measurements indicate that the enhanced performance is due to the additional pseudocapacitance generated by the quinone moieties in lignin. Moreover, a conjugated redoxpolymer poly(aminoanthraquinone) PAAQ, with intrinsic quinone functions and excellentstability, has been combined with lignin and PEDOT resulting in a trihybrid bioelectrode. PEDOT compensates the low conductivity of PAAQ and provides electrical pathways to the quinone groups. The electrochemically generated quinones undergo a two electron, two protonredox process within the biohybrid electrodes as revealed by FTIR spectroelectrochemistry.These remarkable features reveal the exciting potential of a full organic energy storage device with long cycle life. Therefore, supercapacitor devices were designed in symmetric or asymmetric two electrode configuration. The best electrochemical performance was achieved by the asymmetric supercapacitor based on PEDOT+Lignin/PAAQ as the positive electrode and PEDOT/PAAQ as the negative electrode. This device exhibits superior electrochemical performance and outstanding stability after 10000 charge/discharge cycles due to the synergistic effect of the two electrodes. Finally, we have characterized the response of this supercapacitor device when charged with the intermittent power supply from an organic photovoltaic module. We have designed charging/discharging conditions such that reserve power was available in the storage device at all times. This work has resulted in an inexpensive fully organic system witht he dual function of energy conversion and storage.
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| 2. |
- Andersson, Viktor
(författare)
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Electron tomography and optical modelling for organic solar cells
- 2012
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Organic solar cells using carbon based materials have the potential to deliver cheap solar electricity. The aim is to be able to produce solar cells with common printing techniques on flexible substrates, and as organic materials can be made soluble in various solvents, they are well adapted to such techniques. There is a large variation of organic materials produced for solar cells, both small molecules and polymers. Alterations of the molecular structure induce changes of the electrical and optical properties, such as band gap, mobility and light absorption. During the development of organic solar cells, the step of mixing of an electron donor and an electron acceptor caused a leap in power conversion efficiency improvement, due to an enhanced exciton dissociation rate. Top performing organic solar cells now exhibit a power conversion efficiency of over 10%. Currently, a mix of a conjugated polymer, or smaller molecule, and a fullerene derivative are commonly used as electron donor and acceptor. Here, the blend morphology plays an important role. Excitons formed in either of the donor or acceptor phase need to diffuse to the vicinity of the donor-acceptor interface to efficiently dissociate. Exciton diffusion lengths in organic materials are usually in the order of 5-10 nm, so the phases should not be much larger than this, for good exciton quenching. These charges must also be extracted, which implies that a network connected to the electrodes is needed. Consequently, a balance of these demands is important for the production of efficient organic solar cells.Morphology has been found to have a significant impact on the solar cell behaviour and has thus been widely studied. The aim of this work has been to visualize the morphology of active layers of organic solar cells in three dimensions by the use of electron tomography. The technique has been applied to materials consisting of conjugated polymers blended with fullerene derivatives. Though the contrast in these blends is poor, three-dimensional reconstructions have been produced, showing the phase formation in three dimensions at the scale of a few nanometres. Several material systems have been investigated and preparation techniques compared.Even if excitons are readily dissociated and paths for charge extraction exist, the low charge mobilities of many materials put a limit on film thickness. Although more light could be absorbed by increased film thickness, performance is hampered due to increased charge recombination. A large amount of light is thus reflected and not used for energy conversion. Much work has been put into increasing the light absorption without hampering the solar cell performance. Aside from improved material properties, various light trapping techniques have been studied. The aim is here to increase the optical path length in the active layer, and in this way improve the absorption without enhanced extinction coefficient.At much larger dimensions, light trapping in solar cells with folded configuration has been studied by the use of optical modelling. An advantage of these V-cells is that two materials with complementing optical properties may be used together to form a tandem solar cell, which may be connected in either serial or parallel configuration, with maintained light trapping feature. In this work optical absorption in V-cells has been modelled and compared to that of planar ones.
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| 3. |
- Bergqvist, Jonas, 1983-
(författare)
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Optoelectrical Imaging Methods for Organic Photovoltaic Materials and Moduls
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- To achieve a high living standard for all people on Earth access to low cost energy is essential. The massive burning of fossil fuels must be drastically reduced if we are to avoid large changes of our climate. Solar cells are both technologically mature and have the potential to meet the huge demand for renewable energy in many countries. The prices for silicon solar cells have decreased rapidly during the course of this thesis and are now in grid parity in many countries.However, the potential for even lower energy costs has driven the research on polymer solar cells, a class of thin film solar cells. Polymer solar cells can be produced by roll to roll printing which potentially enables truly low cost solar cells. However, much research and development remain to reach that target.Polymer solar cells consist of a semiconducting composite material sandwiched between two electrodes, of which one is transparent, to let the light energy in to the semiconductor where it is converted to electric energy. The semiconductor comprise an intimate blend of polymer and fullerenes, where the nanostructure of this blend is crucial for the photo current extraction.To reach higher solar cell performance the dominating strategy is development and fine tuning of new polymers. To estimate their potential as solar cell materials their optical response have been determined by spectroscopic ellipsometry. Furthermore, optical simulations have been performed where the direction dependency of the optical response of the transparent electrode material PEDOT:PSS have been accounted for. The simulations show reduced electrode losses for light incident at large oblique angles.Moreover, we have shown that a gentle annealing of the active layer induces a local conformational changes of an amorphous polymer that is beneficial for solar cell performance. The active layer is deposited from solution where the drying kinetics determine the final nanostructure. We have shown that using in-situ photoluminescence phase separation can be detected during the drying process while a reflectance method have been developed to image lateral variations of solvent evaporation rate.Imaging methods are important tools to detect performance variations over the solar cell area. For this purpose an intermodulation based photo current imaging method have been developed to qualitatively differentiate the major photo current loss mechanisms. In addition, a 1D LED-array photo current imaging method have been developed and verified for high speed in-line characterization of printed organic solar modules.
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| 4. |
- Bian, Qingzhen, 1988-
(författare)
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Excitonic and charge carrier transport in organic materials and device applications
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- With the potential for future commercial use, organic electronics have been intensively studied for the last few decades. To exploit the next generation of high-performance devices, detailed study of the underlying physics is essential. Excitonic and charge carrier transport plays a critical role in device performance and related studies have attracted a lot of attention in recent decades. This thesis particularly focused on excitonic and charge carrier transport in organic materials and related device applications.In natural light harvesting systems, such as the reaction centers of purple bacteria, quantum coherence has been proposed to be present as a contributor to the related charge and energy transport processes, and almost 100% charge conversion is present in these efficient biological systems. This high energy conversion efficiency inspires the idea that if a similar strategy was used in artificial energy conversion devices such as organic photovoltaics, etc., this could significantly enhance the device’s performance. In the first study, the charge separation process in some donor/acceptor blends was investigated. The contribution of quantum coherence to device performance was studied in detail using several steady state and ultrafast transient techniques. In one efficient donor/acceptor blend, a pronounced coherence of charge separation was identified, which contributed to the enhancement of the photocurrent generation, which finally resulted in efficient device performance.For the light emitting diodes, triplet excitons harvesting plays a critical role in device performance. In the thermally activated delayed fluorescence (TADF) materials, due to an efficient reverse intersystem process from triplet excitons to singlet excitons, the losses due to triplet excitons were suppressed. As a result, a desired high quantum yield has been achieved. To enhance device efficiency, the detailed study of the upconversion physics between triplet and singlet is needed. Previous studies have proposed some physical models to explain this efficient upconversion process, while the nature of this physical process is still under debate and unclear. In my second work, we studied the exciton kinetics in two different TADF materials. These TADF materials were inserted in a protein fibril host, and the resulting protein scaffold was able to modify the geometric configuration of the related TADF molecule. As a result, an enhancement of the photoluminescence quantum yield was achieved.To achieve efficient device performance in organic electronics, the physical processes at the metal/material interface and charge carrier injection/extraction, also play a critical role. Efficient charge injection can be achieved by Ohmic contact, and charge injection/extraction of metal/organic materials has been intensively studied in the last few decades. In my third study, an efficient hole transport material based on the biopolymer DNA was introduced. A hole doping process was found in the hybrid materials and contributes to the Ohmic contacts. The hybrid material can be used in different organic electronics devices, such as field effect transistors, light emitting diodes and solar cells, and thus demonstrates a general application capability.In organic photovoltaics, the loss from the open circuit photovoltages has been an Achilles’ heel for further enhancement of device performance. The voltage loss includes the radiative and non-radiative value, and intensive studies have focused on how to suppress losses from the non-radiative channel. In my fourth study, the non-radiative voltage loss was studied in a series of terpolymer blends and ternary blends. Compared to the ternary blends, a decreased nonradiative loss was found in the terpolymer blends.
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| 5. |
- Bäcklund, Fredrik
(författare)
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Preparation and Application of Functionalized Protein Fibrils
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Many proteins have an innate ability to self-assemble into fibrous structures known as amyloid fibrils. From a material science perspective, fibrils have several interesting characteristics, including a high stability, a distinct shape and tunable surface properties. Such structures can be given additional properties through functionalization by other compounds such as fluorophores. Combination of fibrils with a function yielding compound can be achieved in several ways. Covalent bond attachment is specific, but cumbersome. External surface adhesion is nonspecific, but simple. However, in addition, internal non-covalent functionalization is possible. In this thesis, particular emphasis is put on internal functionalization of fibrils; by co-grinding fibril forming proteins with a hydrophobic molecule, a protein-hydrophobic compound molecule composite can be created that retains the proteins innate ability to form fibrils. Subsequently formed fibrils will thus have the structural properties of the protein fibril as well as the properties of the incorporated compound. The functionalization procedures used throughout this thesis are applicable for a wide range of chromophores commonly used for organic electronics and photonics. The methods developed and the prepared materials are useful for applications within optoelectronics as well as biomedicine.Regardless of the methodology of functionalization, using functionalized fibrils in a controlled fashion for material design requires an intimate understanding of the formation process and knowledge of the tools available to control not only the formation but also any subsequent macroscale assembly of fibrils. The development and application of such tools are described in several of the papers included in this thesis. With the required knowledge in hand, the possible influence of fibrils on the functionalizing agents, and vice versa, can be probed. The characteristic traits of the functionalized fibril can be customized and the resulting material can be organized and steered towards a specific shape and form. This thesis describes how control over the process of formation, functionalization and organization of functionalized fibrils can be utilized to influence the hierarchical assembly of fibrils – ranging from spherical structures to spirals; the function – fluorescent or conducting; and macroscopic properties – optical birefringence and specific arrangement of functionalized fibrils in the solid state. In conclusion, the use of amyloid fibrils in material science has great potential. Herein is presented a possible route towards a fully bottom up approach ranging from the nanoscale to the macroscale.
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| 6. |
- Gabrielsson, Roger
(författare)
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Electroactive Conjugated Polyelectrolytes Based on EDOT From Synthesis to Organic Electronics
- 2012
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Conjugated polyelectrolytes (CP) show interesting electrical and optical properties for organic electronics as well as for life science applications. Their possibilities of supramolecular assembly with nanowire like misfolded proteins, amyloids, as well as synthetic polypeptides or DNA forming conducting nano composites is highly interesting as being a truly bottom up approach for fabrication of OLEDs, photovoltaic’s as well as logic devices.A special class of CPs is that of electroactive cojugated polymers (ECPs), which, due to their structure, will exhibits a unique combination of properties, including the following; electrically conducting, ability to store an electric charge and ability to exchange ions. The positive or negative excess charge can be introduced into the conjugated polymer by means of chemical or electrochemical oxidation/reduction (a process called doping) following the polymerization reaction. In order to preserve overall electroneutrality of the polymer during introduction of excess charge, ionexhange processes occurs between the polymer phase and the surrounding electrolyte solution. This charge/discharge process can be utilized for application such as; pseudo super capacitors (energy storage through oxidation/reduction processes), electro mechanical actuators (convert electrical energy to mechanical energy) and sensors (converts a chemical signal to electrical conductivity).In this thesis we describes the synthetic challenges with ECPs for applications vide supra. These mostly relates to solubility, ionic functionalization, conductivity and macromolecular properties such as size and shape of the ECPs. The key requirement in the synthesis of ECPs is that the conjugated nature of the monomer is conserved in the synthesis process and that insertion of excess charge (doping) can be obtained. This limits both the choice of monomer and the choice of polymerization process. Monomers of great complexity have been synthesized with this careful goal in mind. Furthermore, the development of novel monomers must also target the appropriate functionality for polymerization. As such, most ECP monomers are electron-rich molecules with pendant groups containing pyrroles, thiophenes, or 3,4-ethylenedioxythiophenes. These three well known ECP monomers are excellent additions to conjugated systems as they typically enable electrochemical polymerization and direct the polymerizations toward linear polymers with good stability towards doping.The first topic of this thesis we demonstrate how we can obtain water soluble ECPs with good electrical conductivity by controlling the polymerization techniques and proper ionic functionalization of the monomer. We also show how these polymers can be incorporated by self-assembly with biomolecular templates, such as, DNA and amyloid fibrils, thus generating novel electrically conductive nanowires.The second topics of this thesis demonstrate how hydrogels of ECPs can be used as bioand charge storage materials, were we demonstrate electronically controlled cell release for biology applications. Both applications are based on ECPs ability to ionexhange processes during electrochemical redox reactions. As well as ions, solvent and other neutral molecules may enter the film during charge/discharge processes. This cause a swelling or shrinking of the ECP films and the expansion and contraction of the polymer network in conjugation with the sorption/desorption of solvent molecules and ions can be described in terms of mechanical work.In the first case we were able to synthesize a water soluble ECP with high amphiphilic character. The polymer was immobilized onto a flexible electrode, suitable for cell growth and subjected to a cell growth media. When the desired cell layer was formed we applied a potential to the flexible electrode. This resulted in that the mechanical work of the immobilized ECP during the applied potential overcame the week adhesive forces to the flexible electrode, which resulted in super swelling and disintegration of the ICP and the cell layer could be harvested.In the second case the possibilities of using synthetically modified ECPs as a dopant during electropolymerization of another ECP monomer to obtain a polymer integrated network with high charge density and good charge transport properties. We demonstrate how this polymer network can be used as porous electrodes suitable for supercapacitors.
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| 7. |
- Hamedi, Mahiar
(författare)
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Organic electronics on micro and nano fibers : from e-textiles to biomolecular nanoelectronics
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Research in the field of conjugated polymers (CPs) has led to the emergence of a number of interesting research areas and commercial applications, including solar cells, flexible displays, printed electronics, biosensors, e-textiles and more.Some of the advantages of organic electronics materials, as compared to their inorganic counterparts, include high elasticity, and mechanical flexibility, which allows for a natural integration of CPs into fabrics, making them ideal for e-texile. In this thesis, a novel approach for creating transistors is presented, through the construction of electrolyte gated transistors, directly embedded on functional textile fibers. Furthermore theoretical and experimental results of the integration of functional woven devices based on these transistors are shown. The realization of woven digital logic and design schemes for devices that can be placed inside living tissue, for applications such as neural communication, are demonstrated.Reducing feature sizes in organic electronics is necessity just as in conventional microelectronics, where Moore's law has been the most impressive demonstration of this over the past decades. Here the scheme of self-assembly (SA) of biomolecular/CP hybrid nano-structures is used for creating nano electronics. It is demonstrated that proteins in the form of amyloid fibrils can be coated with the highly conducting polythiophene derivative (PEDOT-S) through molecular self-assembly in water, to form conducting nanowire networks and nanodevices at molecular dimensions. In a second SA scheme, large area patterning of connected micro-nano lines and nano transistors from the conducting polymer PEDOT-S is demonstrated through assembly of these from fluids using soft lithography. Thereby the problems of large area nano patterning, and nano registration are solved for organic electronics. The construction of functional nanoscopic materials and components through molecular self-assembly has the potential to deliver totally new concepts, and may eventually allow cheap mass production of complex three dimensional nano electronic materials and devices.
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| 8. |
- Huang, Hao, 1988-
(författare)
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Quinone-Pyrrole Dyad Based Polymers for Organic Batteries : From Design to Application
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Organic electrode materials are finding increasing use in energy storage devices due to their attractive properties that allow building of flexible and low weight devices in an environmentally friendlier manner than traditional alternatives. Among these organic electrode materials, conducting redox polymers (CRPs), consisting of conducing polymer (CP) with covalently attached redox active pendant groups (PG), have attracted our interests. This is due to the advantageous synergy between CP and PG, e.g. electronic conductivity, high stability and large charge storage capacity. In this thesis polypyrrole has been selected as CP and quinones as PGs. A series of quinone-pyrrole dyad polymers has been synthesized with a variety of quinone substituents, demonstrating the adjustability of quinone formal potentials by choice of substituents. Importantly, in this series we show that the CP-PG redox match, i.e. that the formal potential of the PG is within the conducting region of the CP, is a requirement for fast charge transfer from the electrode to the PGs. Moreover, a series of quinone-pyrrole dyad polymers with various linkers was synthesized, showing that the choice of linker has a pronounced impact on the interactions between the PG and CP. In addition, the temperature dependence of conductance during doping of the polymers reveals the charge transport mechanism. To summarize, the adjustability of the quinone formal potential as well as the fast charge transport in the bulk material ensures the applicability of the CRPs as electrode materials in organic batteries.
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| 9. |
- Kuang, Chaoyang, 1988-
(författare)
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Interface-Assisted Perovskite Modulations for High-Performance Light-Emitting Diodes
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Metal halide perovskites have emerged as a class of promising materials for a wide range of optoelectronic devices. Compared with traditional inorganic and organic semiconductors, perovskite materials can be easily processed via solution-based techniques at low temperatures and exhibit high photo-luminescence efficiency, outstanding colour purity, and superior charge transport properties, showing great promise for cost-effective and high-performance light-emitting diodes (LEDs).Since the first demonstration of room-temperature operating perovskite-based LEDs (PeLEDs) in 2014, various useful strategies on optimizing perovskite emissive materials and device structures have been developed, leading to notably enhanced device performance of PeLEDs during the last several years. Nevertheless, despite rapid progress in improving the external quantum efficiencies (EQEs) of PeLEDs, which are now approaching those of commercialized technologies, the operational stability of state-of-the-art PeLEDs remains poor, presenting a critical challenge for their practical applications and commercialization. Besides, a majority of the optimization strategies demonstrated for PeLEDs derivate from those developed for either perovskite photovoltaics or prevailing light-emitting technologies, e.g., organic- and quantum-dot-based LEDs. Although these strategies are helpful, more comprehensive investigations and in-depth understanding of factors affecting the property of perovskite emissive layers and the device performance of ensuing PeLEDs are highly desirable to foster further advancements of this promising technology.In this thesis, we focus our study on near-infrared PeLEDs based on triiodide perovskite emissive layers processed from precursor solutions. We systematically investigate the critical effects of precursors, substrates, and additives on the film quality of perovskite emissive layers. With the indepth understanding of the perovskite crystallization process, we developed a range of effective interface-assisted strategies on modulating the perovskite emissive layers, which enable us to achieve PeLEDs with high EQEs and excellent long-term operational stability beyond the state-of-the-art.In the first study, we unveiled the synergistic effect of precursor stoichiometry and interfacial reactions for PeLEDs. We reveal that ZnO efficiently deprotonates the organic cations, which promotes the formation of highly emissive perovskites from precursor solution with excess organic components, leading to the achievement of PeLEDs with a high EQE of 19.6 %. In the second study, we presented that such ZnO deprotonation process of excess organic cations can also assist the cation exchange process between cesium-formamidinium (FA-Cs) cation exchange, enabling low-temperature fabrication of pure-phase Cs-FA mixed cation perovskite films with widely tunable emissions peaking between 715 nm and 800 nm as well as high-performance devices with peak EQEs over 15%.In spite of enhanced device efficiency realized by the perovskite crystallization modulation, this ZnO deprotonation process places a detrimental effect on the stability of the PeLEDs, which can be accelerated by Joule heating and high electric fields during the device operation. In the third study, we, therefore, demonstrated the role of ZnO in catalyzing an efficient amidation reaction between incorporated dicarboxylic acid additives and excess FAI, preventing the above-mentioned harmful interfacial reaction. With this strategy, the operational half lifetime of the resulting PeLEDs was improved to 682 hours at 20 mA/cm2 while maintaining a high device efficiency of 18.6%.In the last work, we emphasized that the rational design of molecular reactions between two additives (diamine and triacrylate) and perovskite components with the assistance of ZnO substrates can subsequently eliminate the negative effect introduced by additive, reduce the defect density and enhance the crystal orientation in the perovskite emissive layers. The rational understanding of interfacial interactions between perovskite, additives, and ZnO, enabled us to achieve PeLEDs with a device efficiency of 23.8% as well as an outstanding operational stability T70 (reduction to 70% of initial efficiency) lifetime of 290 hours at 20 mA/cm2.The study in this thesis developed effective interface-assisted modulation strategies for high-quality perovskites towards highly efficient and stable PeLEDs for commercialization. A thorough understanding of perovskite chemistry-property-performance modulation assisted by interfaces is indispensable for the future development of PeLEDs and our study took an important step.
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| 10. |
- Liu, Lianlian, 1988-
(författare)
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Renewable and Scalable Energy Storage Materials Derived from Quinones in Biomass
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Currently there is an urgent need to reduce the use of fossil fuels, and efficient sustainable energy harvesters from sun and wind have been developed and are widely used for electricity generation. Storage of electrical energy is accordingly necessary to accommodate the time varying supply of wind and solar electricity. Quinones (Q) are attractive as energy storage materials due to their high theoretical charge density and the renewable and abundant source – biomass. Plant-based biomass materials – such as lignin and humic acids – contain redox active Q-groups that potentially could be used for electricity storage instead of simply burning the biomass, which releases CO2, CH4, NOx, and SOx. Lignin accounts for 20-30% of the biomass weight and contains a sizable fraction of Q-structures. However, utilization of lignin for large scale energy storage is still a challenging task, as lignin is electrically insulating and conductive materials are required to get access to the generated electrons in the bulk. Various relatively expensive materials, such as conductive polymers and various carbon materials (carbon nanotubes, active carbon, graphene, etc.) have been combined with lignin, resulting in hybrid materials for energy storage. However, as the scale required for production of charge storage devices is huge it is of outmost importance to reduce the cost and therefore investigate low-cost conductive materials. In this thesis, common graphite flakes are combined with the lignin derivative lignosulphonate (LS) via a solvent free ball-milling process, followed by treatment with water and resulting in a paste that can be processed into electrodes. Similarly, humic acid derived from peat, lignite that contains a large amount of Q-groups is also fabricated into electrode with graphite via the ball-milling process. In order to further reduce the impact on environment during the extraction of Q-materials from biomass, barks that contain as much as 30% of lignin are directly used for energy storage via co-milling with pristine graphite to generate the biomass/graphite hybrid material electrodes. However, larger weight fraction of Q are required to further improve the electrochemical performance of these electrodes and Q chemicals (QCs) that also originate from biomass are introduced to fabricate the QCs/graphite electrodes with an increased capacity. Additionally, self-discharge mechanism is studied on the LS/graphite hybrid material electrodes, which provides instructions to achieve a low self-discharge rate.Overall, this study has brought us one step forward on the establishing of scalable, sustainable, and cost-effective energy storage systems using aqueous electrolytes.
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