The building sector is one of the sectors that consume most energy in Sweden. Sweden aims thereby to reduce energy use in buildings by 20% by 2020 and 50% by 2050. To achieve these goals, more energyefficient buildings must be produced, and more energy-efficient measures must be implemented on existing buildings. Electrochromic windows are claimed to reduce the need for heating and cooling, as well as the need for artificial lighting. However, there is limited research on smart windows in the Nordic climate.   This thesis examines electrochromic windows in Sweden, using the IDA ICE 4.7.1 simulation program. The study includes a comparative analysis of an office building model with conventional windows and motorized awnings, versus electrochromic windows with different control strategies, to investigate the building’s impact. In total, eight different scenarios are simulated in Stockholm, Umeå and Malmö. The electrochromic window scenarios consist of control algorithms where the windows are always on or off, as well as algorithms that respond to sunlight, daylight, operative temperature or scheduling. The conventional windows and awnings scenario represents the reference building. The Swedish building certification system "Miljöbyggnad" is used as a guideline for evaluating energy use, heating power demand, solar heat load, thermal climate, and daylight.   The results show that electrochromic windows have little impact on the building. None of the scenarios succeed in obtaining higher certification than BRONZE, which corresponds to the authority's requirements for newly built buildings. However, electrochromic windows have a significant effect on the solar heat load and the lux level in the building, but unfortunately not enough to get a better building grade. There is no remarkable difference between the indicators and scenarios. Furthermore, the results show that scenarios that are shaded often (Always on, Daylight Control, Solar Control strategy) achieve GOLD ratings in solar heat load, but have the least impact on energy consumption and vice versa. Always off, Operative Temperature Control, and Schedule, Façade and Window strategy upgrades by one level in energy use. This confirm previous studies that claim that electrochromic windows have the greatest potential in energy saving in hot climate. This explains why there is hardly any difference between scenarios and cities.   The thesis lacks specific costs for electrochromic windows. Thus, the cost estimate is based on generalizations and assumptions, in which the cheapest and most expensive options are investigated. If the building has well-functioning windows and awnings, it is not cost effective to switch to electrochromic windows, since the payback time is far too long. But if the building was between conventional windows and electrochromic windows during the planning phase, it might be interesting to conduct a detailed cost analysis. According to this study, the Operative Temperature Control strategy saves approximately 6 333kr during the simulation period. The cost differences between conventional windows with motorized awnings, and the cheapest version of electrochromic windows is around 60 000kr. This would provide a refund within 10 years, given that energy prices, energy consumption and currency value are the same. After that, the window would cut the energy costs in the form of saved energy.   However, the study concludes that electrochromic windows are not necessary in this project from a Miljöbyggnad perspective, since the building grade remains the same and the economic gain is uncertain. / Byggnadssektorn är en av de sektorer som använder mest energi i Sverige. Därmed har Sverige som mål att minska energianvändningen i byggnader med 20% år 2020, och 50% år 2050. För att uppnå dessa mål måste fler energieffektiva byggnader produceras, samt fler energieffektiva åtgärder måste genomföras på befintliga byggnader. Elektrokroma fönster hävdas minska behovet av uppvärmning och kylning, samt behovet av artificiell belysning. Det finns dock begränsad forskning om smarta fönster i det nordiska klimatet.   Detta examensarbete undersöker elektrokroma fönster i Sverige, med hjälp av simuleringsprogrammet IDA ICE 4.7.1. Arbetet omfattar en jämförande analys av en kontorsbyggnadsmodell med vanliga fönster och motoriserade markiser, kontra elektrokroma fönster med olika kontrollstrategier, för att undersöka byggnadens påverkan. Sammanlagt simuleras åtta olika scenarier i Stockholm, Umeå och Malmö. De scenarier med elektrokroma fönster består följaktligen av kontroll algoritmer där fönsterna är alltid på eller avstängda, samt algoritmer som reagerar på solljus, dagsljus, operativa temperatur eller schemaläggning. Scenariot med vanliga fönster och markiser representerar referensbyggnaden. Det svenska byggnadscertifieringssystem ”Miljöbyggnad” används som riktlinje för evaluering av energianvändning, värmeeffektbehov, solvärmelast, termiskt klimat, och dagsljus. Resultaten visar att elektrokroma fönster har liten påverkan på byggnaden. Ingen av scenarierna lyckas få högre certifiering än BRONS, vilket motsvarar myndighetens krav på nybyggda byggnader. Dock så har elektrokroma fönster signifikant inverkan på solvärmelasten och lux nivån i byggnaden, men tyvärr inte tillräckligt för att få ett bättre byggnads betyg. Det är ingen anmärkningsvärd skillnad sinsemellan indikatorerna och scenarierna. Vidare visar resultaten att scenarier som är skuggade ofta (Alltid på-, Dagljuskontroll-, Solljuskontrollstrategin) uppnår GULD betyg inom solvärmelast men har minst inverkan på energiförbrukningen och vice versa, Alltid av-, operativa temperaturkontroll, samt schemaläggning, fasad och fönster strategin uppgraderas ett steg inom energianvändning. Detta styrker tidigare studier som påstår att elektrokroma fönster har störst potential i energibesparing i varma klimat.   Detta förklarar den minimala skillnaden av byggnadens påverkan mellan städer och scenarier. I denna rapport saknas specifika kostnader för elektrokroma fönster. Därmed baseras kostnadsuppskattningen på generaliseringar och antagande, där billigaste och dyraste alternativet undersökts. Om byggnaden har väl fungerande fönster och markiser, är det inte kostnadseffektiv att byta till elektrokroma fönster, då återbetalningstiden är alldeles för lång. Men om byggnaden stod mellan vanliga fönster och elektrokroma fönster i planeringsfasen kan det vara intressant att göra en noggrann analys. Enligt denna studie så sparar den Operativa Temperatur strategin ca. 6 333kr per år. Det skiljer ca 60 000kr mellan vanliga fönster med markiser, och elektrokroma fönster. Detta skulle ge en återbetalning inom 10 år förutsatt att energipriserna, energiförbrukningen samt valuta värdet är desamma. Därefter skulle fönstret minska utgifterna i form av sparad energi.   Slutsatsen är dock att elektrokroma fönster inte är nödvändiga i detta projektet från en Miljöbyggnads synpunkt, eftersom att det inte förbättrar byggnadsbetyget. Dessutom kvarstår osäkerheten med kostnader.

In this study three different 3-ester substituted thiophene monomers were synthesized via esterification reaction of 3-thiophene ethanol with adipoyl chloride or sebacoyl chloride or octanoyl chloride in the presence of triethylamine at 00C. Characterizations of the monomers were performed by 1H-NMR, 13C-NMR, FTIR, DSC, TGA techniques. Electrochemical behavior of the monomers both in presence or absence of BFEE were studied by cyclic voltammetry. Results showed the astonishing effect of BFEE on the polymerization, where free standing films of the homopolymers could be synthesized. Copolymers of the monomers with thiophene or 3-methyl thiophene were synthesized at constant potential electrolysis and the resultant polymers were characterized by FTIR, DSC, TGA, SEM and conductivity measurements. Second part of the study was devoted to investigate the one of most interesting property of conducting polymers, the ability to switch reversibly between the two states of different optical properties, &lsquo / electrochromism&rsquo / . In recent years there has been a growing interest in application of conducting polymers in electrochromic devices. Thus, electrochromic properties of the synthesized conducting polymers were investigated by several methods like spectroelectrochemistry, kinetic and colorimetry studies. Spectroelectrochemistry experiments were performed in order to investigate key properties of conjugated polymers such as band gap, maximum absorption wavelength, the intergap states that appear upon doping and evolution of polaron and bipolaron bands. Switching time and optical contrast of the homopolymers and copolymers were evaluated via kinetic studies. Results implied the possible use of these materials in electrochromic devices due to their satisfactory electrochromic properties like short switching time and stability. Generally the homopolymers displayed color changes between yellow, green and blue colors upon variation of applied potentials. Fine tuning of the colors of the polymers were accomplished by techniques like copolymerization and lamination. These studies were supported with experiments like spectroelectrochemistry and FTIR. Results showed the possible control of the color of the electrochromic material in a predictable, controlled and reproducible manner. Yet, it was possible to achieve different tones of yellow, green, orange color in neutral state of these materials. As the last part of the study, dual type electrochromic devices based on polymers of 3-ester substituted thiophenes with poly(3,4-ethylenedioxythiophene) were constructed, where the former and the later functioned as anodically and cathodically coloring layers respectively. Spectroelectrochemistry, switching ability, stability, open circuit memory and color of the devices were investigated and the results revealed that these devices have satisfactory electrochromic parameters.

Electrochromic (EC) glazing has emerged as an alternative to traditional forms of glazing. It has the potential to enable occupants to control daylight ingress without the use of blinds, giving users more access to daylight with all its inherent benefits. Research efforts to date have been mainly focussed on the potential of EC glazing as an energy saving technology through the reduction of electric lighting and air conditioning energy loads, using scale models, computer simulations and full scale test rooms. Few studies have considered the user experience of the technology, and none of the studies that have included data from human participants have been carried out in a real-world research setting over a long-term period. Thus, there is a general lack of understanding regarding the performance and suitability of EC glazing in real-world working environments. To address this gap in research, a new study of EC glazing was undertaken, looking at the experience of occupants working in an office that had been retrofitted with EC-glazed windows. The retrofit was the first of its kind in the UK, and provided an opportunity to study the user experience of EC glazing in a real-world setting over a longitudinal period. The aims of the study were to gain new insights into the experience of users of EC glazing, and to learn about the practicalities of installing it. A number of research questions were defined, leading to a mixed methods data collection programme, carried out over a period of almost 18 months. The data collection encompassed data from the occupants as well as from the physical environment, and was designed in response to the constraints of the site and occupants, as well as the aims of the research enquiry. The resulting data set includes a valuable record of occupant experiences and behaviour, as well as detailed information about environmental conditions at key times. A number of contextual factors influencing the effectiveness of EC glazing were identified. The outcomes of this research provide a new understanding of the user experience of EC glazing, and thus can inform further technological development and benefit future installations.

<p> In an era of advancing printed electronics, solution-processable organic semiconductors continue to make significant strides in electronic and optoelectronic applications. Electrochromic (EC) technology, which encompass reversible optical modulation under electrochemical biasing, has progressed rapidly over the past half-century and developed into niche commercial-scale devices for auto-tinting glasses as well as low-power, non-emissive displays. To utilize the advantages of organic electrochromic materials in next-generation devices, it is imperative to understand their fundamental material properties, interactions with other device components, and the underlying electrochemistry that governs the overall optical and electrochemical response of the complete electrochromic device. This dissertation presents a discussion on the synergistic role of organic electrochromes, charge-balancing layers and electrolytes in determining two key performance metrics, namely the optical contrast and operational stability, of an electrochromic device (ECD). The absorption features of colored-to-transmissive switching conjugated polymers have been investigated by exploring material design strategies in conjunction with analytical approaches to optimize and enhance the optical contrast. In parallel, transmissive redox-active radical polymer counter electrodes have been developed as compatible charge-balancing layers and integrated into devices by pairing with electrochromic polymers (ECPs) to achieve stable and high-contrast optical modulation. Electrochemical activity of both conjugated and radical polymer electrodes in different ionic and solvent environments have been further examined to understand material-electrolyte interactions governing mixed ionic-electronic conduction. Finally, a small molecular approach to realizing transparent-to-colored electrochromism is discussed, where distinct substituent-induced degradation pathways of conjugated radical cations were revealed. Overall, this research aims to assist future development of robust, ultra-high contrast organic electrochromic platforms.  </p>

ABSTRACT SYNTHESIS AND ELECTROCHROMIC PROPERTIES OF CONDUCTING POLYMERS OF SUCCINIC ACID BIS-(2-THIOPHEN-3-YL-ETHYL) ESTER AND THEIR USE IN ELECTROCHROMIC DEVICES Sa&ccedil / an, Lale M.Sc., Department of Chemistry Supervisor: Prof. Dr. Levent Toppare June 2006, 59 pages A new monomer / succinic acid bis-(2-thiophen-3-yl-ethyl)ester (SATE) was synthesized through the esterification reaction of 2-thiophen-3-yl-ethanol and succinyl chloride. The chemical structure of monomer was characterized via Nuclear Magnetic Resonance Spectroscopy (NMR) and Fourier Transform Infrared Spectroscopy (FTIR). Electrochemical behaviors of SATE alone and SATE in the presence of thiophene were studied by cyclic voltammetry (CV). The synthesis of homopolymer and copolymer were achieved via constant potential electrolysis. Both homopolymer (PSATE) and copolymer [P(SATE-co-Th)] were characterized by various techniques including cyclic voltammetry, FTIR, Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC), Thermal Gravimetry Analysis (TGA) and UV-VIS Spectrophotometer. Conductivities of samples were measured by four probe technique. The electrochromic properties of the polymers were investigated via spectroelectrochemistry, colorimetry and switching studies. In addition, dual type electrochromic devices (ECDs) composed of PSATE, P(SATE-co-Th) and poly(3,4-ethylenedioxythiophene) (PEDOT) were constructed and evaluated. Spectroelectrochemistry, switching ability and stability of the devices were investigated by UV-Vis Spectrophotometer and Cyclic Voltammetry. They have shown to possess good switching times, reasonable contrasts, high stabilities and optical memories.

A new monomer / 1-(4-Nitrophenyl)-2,5-di-2-thienyl-1H-pyrrole SNSNO2 was synthesized through the Knorr-Paal condensation reaction of 1,4-di-2-thienyl-1,4-butanedione and p-nitroaniline. The chemical structure of monomer and polymer were characterized via Nuclear Magnetic Resonance Spectroscopy (NMR) and Fourier Transform Infrared Spectroscopy (FTIR). Chemical polymerization produced a polymer which was completely soluble in organic solvents. Electrochemical behaviors of SNSNO2 and SNSNO2 in the presence of EDOT were studied by cyclic voltammetry (CV). The synthesis of homopolymer and copolymer were achieved via constant potential electrolysis. Both homopolymer P(SNSNO2) and copolymer P(SNSNO2-co-EDOT) were characterized by various techniques including cyclic voltammetry, FTIR, Scanning Electron Microscopy (SEM) and UV-VIS Spectrophotometer. Conductivities of samples were measured by four probe technique. The electrochromic properties of the polymers were investigated via spectroelectrochemistry, colorimetry and switching studies. In addition, dual type electrochromic devices (ECDs) composed of P(SNSNO2), P(SNSNO2-co-EDOT) and poly(3,4-ethylenedioxythiophene) (PEDOT) were constructed and evaluated. Spectroelectrochemistry, switching ability and stability of the devices were investigated by UV-Vis Spectrophotometer and Cyclic Voltammetry. They have shown to possess good switching times, reasonable contrasts and high stabilities.

Terepthalic acid bis-(2-thiophen-3-yl-ethyl)ester (TATE) was synthesized through the reaction of 2-thiophen-3-yl-ethanol and terepthaloyl chloride. Electrochemical behavior of the TATE and TATE in the presence of thiophene were studied by cyclic voltammetry (CV). The chemical structure of monomer is characterized via Nuclear Magnetic Resonance Spectroscopy (NMR) and Fourier Transform Infrared Spectroscopy (FTIR). Homopolymer of TATE was synthesized by galvanostatic and potentiostatic methods, and copolymerization of TATE with thiophene was achieved via potentiostatic method. Both homopolymer (PTATE) and copolymer [P(TATE-co-Th)] were characterized by various techniques including cyclic voltammetry, FTIR, Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC), Thermal Gravimetry Analysis (TGA) and UV-VIS Spectrophotometer. Conductivities of samples were measured by four probe technique. Electronic band gap of polymers measured as the onset of the &amp / #960 / -&amp / #960 / * transition using spectroelectrochemical analysis and colorimetry studies were investigated. Dual type polymer electrochromic devices (ECDs) based on PTATE, P(TATE-co-Th) and poly(3,4-ethylenedioxythiophene) (PEDOT) have been constructed. Spectroelectrochemistry, switching ability and stability of the devices were investigated by UV-Vis Spectrophotometer and Cyclic Voltammetry.

Electrochromic thin films can effectively regulate the visible and infrared light passing through a window, demonstrating great potential to save energy and offer a comfortable indoor environment in buildings. However, long-term durability is a big issue and the physics behind this is far from clear. This dissertation work concerns two important parts of an electrochromic window: the anodic and cathodic layers. In particular, work focusing on the anodic side develop a new Ni oxide based layers and uncover degradation dynamics in Ni oxide thin films; and work focusing on the cathodic side addresses materials rejuvenation with the aim to eliminate degradation. In the first part of this dissertation work, iridium oxide is found to be compatible with acids, bases and Li+-containing electrolytes, and an anodic layer with very superior long-term durability was developed by incorporating of small amount (7.6 at. %) of Ir into Ni oxide. This film demonstrated sustained cycle-dependent growth of charge density and electrochromic modulation even after 10,000 CV cycles. The (111) and (100) crystal facets in Ni oxide are found to possess different abilities to absorb cation and/or anion, which yields different degrees of coloration and this is very significant for the electrochromic properties. The degradation of charge capacity in Ni oxide has an inevitable rapid decay in the first hundreds of cycles, subsequently combined with a more gradual decay, which is independent of applied potential and film composition. The consistent phenomenon can be very well modeled by power-law or stretched exponential decay; however the two models are indistinguishable in the current stage. Interestingly, in both models, the power-law exponent is 0.2 ≤ p ≤ 0.8, with most of the values around 0.5, in line with normal or anomalous diffusion models. The second part of dissertation work deals with cathodic WO3 and TiO2. WO3 suffers from ion trapping induced degradation of charge capacity and optical modulation upon electrochemical cycling. This speculation is strongly supported by direct evidence from Time-of-Flight Elastic Recoil Detection Analysis (ToF-ERDA). Most importantly, this ion trapping induced degradation can be eliminated by a galvanostatic de-trapping process. Significant ion-trapping takes place when x exceeds ~0.65 in LixWO3. The trapped ions are stable in the host structure, meaning that the ions cannot de-trap without external stimuli. The similar work done on TiO2 significantly complements and extends the work on the recuperation of WO3; the difference is that the trapped ions in host TiO2 seem to be less stable compared with the trapped ions in WO3.     Overall, this dissertation presents a refined conceptual framework for developing superior electrochromic windows in energy efficient buildings.

A new sensor technology based on optical diffraction of visible light shows promise for sensing metal ions and other species that employ chemically-responsive metal oxide and conducting polymer grating elements. These materials undergo reversible redox processes upon interaction with a chemical analyte that subsequently induces changes in the materials refractive index. The two key design parameters of this sensing technique involve preparation of micropatterned sensor elements and the evaluation of appropriate wavelengths for detection of diffracted light. Much of the ability to “tune” a desired sensing response is dictated by the understanding of how factors of size, dimension, crystallinity, morphology, porosity, and heterogeneity influence analyte/sensor interactions (i.e., adsorption, binding, and transport). The effect of composition, structure, and morphology of MoO₃, WO₃, Moₓ W₁₋ₓO₃, IrOₓ and polyaniline grating materials on chemical, electrochemical and optical properties of these systems will be examined by a range of spectroscopic and electrochemical techniques. Comprehensive evaluation and correlation of materials’ optical properties to diffraction-based detection will advance understanding of the capabilities and limitations for the diffraction-based sensing methodology. This information can then used to determine optimal sensing parameters to improve detection limits, enhance sensitivity and increase the dynamic range for detection of model analytes. / text

Neste trabalho, reportamos a síntese sonoquímica e a caracterização de nanopartículas de hexacianoferrato de cobre para a fabricação de filmes ultrafinos com expessura controlada. Aproveitando-se da sua esturutra nanométrica e do excesso de carga superficial negativa, os métodos de imobilização propostos foram a deposição eletrostática camada por camada (LBL), utilizando-se o PAH como polieletrólito positivo (hidrocloreto de polialilamina); e a deposição eletroforética que utiliza um campo elétrico para que partículas carregadas em suspensão sejam atraídas para a superfície do eletrodo. Os eletrodos modificados pelas nanopartículas de hexacianoferrato de cobre foram estudados com respeito às suas propriedades eletrocatalíticas e eletrocrômicas. O hexacianoferrato de cobre (HexFeCu) possui algumas características interessantes como a oxidação eletrocatalítica do peróxido de hidrogênio a baixos potenciais e com a vantagem de ser eletroativo em meios contendo Na+. A utilização desse composto estruturado nanometricamente proporciona ainda uma grande área superficial podendo acentuar suas características eletrocatalíticas. Além da aplicação em biossensores amperométricos, também foi possível a sua utilização em dispositivos eletrocrômicos, ao se perceber que o material mudava de cor ao ser reduzido ou oxidado, demonstrando alta reversibilidade, durabilidade eletrocrômica além de uma boa aderência das camadas de nanopartículas eletrostaticamente depositadas ao substrato de ITO. / In this work, the sonochemical synthesis and the characterization of copper hexacyanoferrate nanoparticles for producing ultra thin films with controlled thickness is reported. Due to its nanometric structure and the excess of superficial negative charges, the proposed immobilization methods were the electrostatic deposition layer by layer (LBL), using the PAH as a positive polyelectrolyte Poly(allylamine hydrochloride) and the electrophoretic deposition which uses an electric field in order to attract the charged particles to the electrode surface. The study of the electrodes modified by the copper hexacyanoferrate nanoparticles was focused in its electrocathalytic and electrochromic properties. Copper hexacianoferrate (HexFeCu) presents some interesting properties like the electrocatalytic reduction of hydrogen peroxide at low potential conditions with the advantage of being electroactive in media containing Na+. The utilization of this nanometrically-structured compound provides a very large surface area, enhancing its catalytic properties. Besides its use in amperometric biosensors, it was also possible its use in electrochromic devices because color changes observed during redox cycles, demonstrating high reversibility, electrochromic durability and due to high adherence of nanoparticles to the ITO electrode.