Dissertations / Theses on the topic 'Metal-free dye'
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1
Siu, Chi Ho. "Metallated and metal-free molecular dyes for dye-sensitized solar cells." HKBU Institutional Repository, 2014. https://repository.hkbu.edu.hk/etd_oa/96.
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The molecular design, synthesis and spectroscopic characterization of a series of ruthenium(II), metal-free and platinum(II) photosensitizers were discussed. The applications of some of these compounds in dye-sensitized solar were also outlined. To start with, a brief overview on the background of dye-sensitized solar cells (DSSCs) was presented in Chapter 1. In Chapter 2, a series of new thiocyanate-free ruthenium(II) cyclometalated complexes with different ligands were successfully synthesized and some of them were fully characterized by spectroscopic and computational methods. The nature of cyclometalating ligands effectively tunes the properties of the metal complexes and the resulting DSSC performance. In Chapter 3, new di-anchoring organic dyes have been synthesized and characterized. This molecular design strategy can significantly enhance the . value because this successfully inhibits the undesirable charge combination and prolongs the electron lifetime. The discoveries open up a new avenue to the evolution of organic sensitizers and the optimization of bridged di-anchoring dyes for highly efficient co-adsorbent-free DSSCs. In Chapter 4, a series of new thiophene-free platinum sensitizers for the application of DSSCs was developed. Four unsymmetrical platinum(II) di-acetylide complexes containing phenothiazine moiety with different donor units were designed and synthesized. These photosensitizers were fully characterized by spectroscopic as well as computational studies and also successfully employed in DSSC fabrication. These findings provided positive evidence that platinum-acetylide complexes have a great potential and prospect for the use as promising metal-based photosensitizers in DSSC applications. Finally, Chapters 5 and 6 present the concluding remarks and the experimental details of the work described in Chapters 2–4.
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Bopegedera, A. M. Ranjika Priyadarshi. "Dye laser and diode laser spectroscopy of gas phase free radicals." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184695.
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The gaseous free radicals, alkaline-earth metal monoalkylamides, monoacetylides, monoformamidates and monopyrrolidates, consisting of a metal atom (Ca or Sr) bonded to a single ligand, were synthesized in a Broida oven. The electronic and vibrational structures of these molecules were studied by low-resolution laser spectroscopy techniques. These inorganic molecules are ionic, well represented by the structure M⁺L⁻ (M = Ca, Sr: L = ligand). Three electronic transitions were identified for the metal monoalkylamides and the metal monoformamidates. The formamidate anion bonds to the metal in a bidentate fashion through the oxygen and nitrogen atoms. Two electronic transitions were observed for the metal monopyrrolidates. The pyrrolide anion ring bonds to the metal to provide these "open-faced sandwich" type molecules with pseudo-C₅ᵥ symmetry. For the metal monoacetylide molecules, only one electronic transition (Ā²Π-Ẋ²Σ⁺) was observed. Several vibrational frequencies were determined for these inorganic molecules from the low-resolution spectra. The Ā²Π-Ẋ²Σ⁺ transition of the calcium monoacetylide molecule was rotationally analyzed at high-resolution using the filtered laser excitation spectoscopy technique. The rotational line positions were fitted to a ²Π-²Σ⁺ Hamiltonian to obtain several rotational constants. The calcium-carbon bond length in CaCCH was calculated for the ground (2.248 Å) and excited (2.200 Å) electronic states. The vibration-rotation spectra of the gaseous bismuth hydride and bismuth deuteride molecules were recorded, using a diode laser system. The 1-0 fundamental band and several hot bands with Δv-1 were rotationally analyzed. The rotational line positions were fitted first, to a Dunham energy expression and then to a ³Σ⁻ Hamiltonian, to obtain ground state rotational constants. The bismuth-hydrogen (deuterium) bond distance was calculated to be 1.809 Å (1.807 Å).
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Bahojb-Allafan, Babak. "The development of a metal-free, tannic acid-based aftertreatment of nylon 6.6 dyed with acid dyes." Thesis, University of Leeds, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.699235.
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During the course of this project, a variety of different areas dealing with the aftertreatment of nylon 6.6 dyed with commercial acid dyes was investigated in an attempt to increase the fastness of dyeings to wet treatment. Protease enzyme was used in conjunction with tannic acid in a single-bath, two stage aftertreatment for nylon 6.6 dyed with acid dyes. The effectiveness of this tannic acid/enzyme aftertreatment was comparable to that of six established aftertreatments namely four commercial syntans, the traditional full backtan and a tannic acid/tin system. The metal-free, tannic acid/enzyme aftertreatment offers a potentially more environmentally acceptable alternative to the antimony-based full backtan aftertreatment, as well as formaldehyde-based syntans and tin-derived system. The effectiveness of the newly developed tannic acid/enzyme aftertreatment in improving the fastness to repeated washing of commercial acid dyes on nylon 6.6 was measured against that of a traditional full backtan aftertreatment. The efficiency of the tannic acid/enzyme system was examined under different aftertreatment conditions including temperature, pH and time. The aftertreatment created a system that was free from any heavy metals and environmentally friendly.
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Anwar, Hafeez. "Precious Metal-free Dye-sensitized Solar Cells." 2013. http://hdl.handle.net/10222/42686.
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Exploring new technologies that can meet the world’s energy demands in an efficient and clean manner is critically important due to the depletion of natural resources and environmental concerns. Dye-sensitized solar cells (DSSCs) are low-cost and clean technology options that use solar energy efficiently and are being intensively studied. How to further reduce the cost of this technology while enhancing device performance is one of the demanding issues for large scale application and commercialization of DSSCs. In this research dissertation, four main contributions are made in this regard with the motivation to reduce further cost of DSSC technology. Firstly, ~10% efficiencies were achieved after developing understanding of key concepts and procedures involved in DSSCs fabrication. These efficiencies were achieved after step-by-step modifications in the DSSC design. Secondly, carbon nanotubes (CNTs) were successfully employed as an alternative to Pt in the counter electrodes of DSSCs. DSSCs fabricated with CNTs were ~86% as efficient as Pt-based cells. Non-aligned CNTs were successfully grown using four different CVD methods and finally, multi-walled vertically aligned CNTs (MW-VACNTs) were synthesized using water-assisted chemical vapor deposition (WA-CVD). Thirdly, carbon derived from pyrolysis of nanocrystalline cellulose (NCC) was successfully employed in counter electrodes of DSSCs instead of Pt. DSSCs with NCC were ~58% as efficient as Pt-based DSSCs. Fourthly, novel organic metal-free dyes were designed and employed instead of commonly used Ru-based dyes. DSSCs with these novel sensitizers were ~62% as efficient as those using the conventional Ru-based dyes. Characterization techniques including current-voltage measurements, scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), cyclic voltammetery (CV), thermogravimetric analysis (TGA), small angle x-ray scattering (SAXS), atomic force microscopy (AFM) and x-ray photoelectron spectroscopy (XPS) were used.
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Huang, Shin-Tang, and 黃勢棠. "Metal-Free Organic Dyes for Efficient Dye-Sensitized Solar Cell." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/fnh8g6.
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碩士中國文化大學
應用化學研究所
96
Two series (Cy and An) of dyes containing a cyanovinyl entity and an anthracene with alkoxy substituents at the 9 and 10 positions, respectively, as the spacer have been synthesized and characterized. Dye-sensitized solar cells (DSSCs) using these dyes as the sensitizers exhibited good efficiencies. The efficiencies of the devices based on Cy series range from 3.48-4.92%, and those based on An series range from 4.17-4.69%. These values which reach 45-70% and 59-67%, respectively, with respect to that of N719-based device fabricated under similar conditions. In general, a better DSSC performance was achieved in molecules with a shorter molecular structure and higher light harvesting. The cyanovinyl entity (Cy series), especially in the long molecular structure, where the cyanovinyl group is away from the electron donating amine by two or more aromatic groups, may behave as a charge trap. This argument was supported by theoretical computations. A positive correlation could be obtained from the theoretically calculated product of oscillator strengths and the charge shift at the cyanoacrylic acid group and the short-circuit currents in the DSSCs. The rigid anthracene segment in An series compounds. The anthracene with alkoxy substituents may cause thiophene moiety hamper the charge transfer and results in lower open-circuit voltages and short-circuit currents of the solar cells.
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Hsu, Shuo-Fu, and 徐碩甫. "Development of Metal-Free Organic Dyes for Highly Efficient Dye-Sensitize Solar Cells." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/59226647164338013933.
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碩士國立高雄大學
應用化學系碩士班
102
Recent years due to extensive use of fossil fuels, we can imagine in the next few decades, fossil fuels will be exhausted one day. Due to the severe impact brought by “energy crisis”, it is inevitable to discover and develop renewable energy. Among all of the renewable energy, solar energy is the center of attention and it will be the future trend. Wherein Dye-Sensitize solar cells due to its low production cost, flexibility, large industrial potential and large-scale production, thus, it gets extremely attention and high hopes. In the design of this study was to investigate the two functional groups with organic dye amine. Using the method of synthesis of furan derivatives subject and using Suzuki-Miyaura coupling reaction of synthesis coupled with amine functional groups, and will have the effect of electron donating and with an electron-withdrawing effect of the molecule doped into the body which, to increase the charge transfer on the body and increase its spectral absorption range, while on the other side chain embedded with thiophene molecule material can be used to adjust the material bands, enhance its properties, and increase their solar photons absorption ability and then transform the electron on TiO¬2. The study intends to generate several amine group dye structure utilizes low band gap and photon characteristics in two dimension D-π-A system. This study intends to design two structures with amine dye molecules which poses superior light absorption ability, so in the design of two-dimensional structure of dye can control HOMO and LUMO energy level individually. Therefore, the appropriate energy levels can be regulated and an electrolyte to coordinate with TiO¬2 and improve their conditions of the stack structure which can be significantly improved electron transfer between molecules and molecules.
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Chang, Chun-Chi, and 張鈞齊. "Theoretical Studies of Star-shaped Metal-free Dye-sensitized Solar Cell Organic Dyes." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/66136092144547200044.
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碩士淡江大學
化學學系碩士班
103
In this study, we designed a series of metal-free dye-sensitized solar cell (DSSC) organic dyes with star-shaped system ((EDG1)2-EDG2-π-EWG), incorporating with different moiety, such as auxiliary electron-donating groups (EDG1), mainly electron-donating group (EDG2), π-conjugated linker moiety and electron-withdrawing groups (EWG). Our calculated results were calculated by the density functional theory (DFT/B3LYP) and time-dependent density functional theory method with 6-31G(d) basis set. Our calculated results exhibited a good agreement with experimental data. In different EDG1 system, the stronger auxiliary electron-donating groups can make an effect to influence the molecular to get higher EHOMO, large absorption wavelength, large the free energy change for the electron injection, and longer lifetime. These calculated results of designed molecules show that the TPA series of PY and the DPBF series of DPP have a better performance, and may be used as potential sensitizers in the DSSC application. In different EWG system, the stronger acceptor groups can make an effect to influence the molecular to get lower ELUMO, smaller open circuit voltage. Moreover, when the molecular transition configurations is effective charge transfer excitation, electron distribution extend to anchoring group of dye, electron will injected efficiently to TiO¬2. These calculated results of designed molecules show that the TPA and DPBF series of C have a better performance, and may be used as potential sensitizers in the DSSC application.
8
Lin, Yeh-Yung, and 林燁雍. "Metal-free Sensitizers Approach for High Performance Dye-sensitized Solar Cells." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/60806421969967380874.
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博士國立臺灣大學
化學工程學研究所
102
New organic dyes were developed and used as the sensitizers for the dye-sensitized solar cells (DSSCs). Different approaches (co-sensitized, co-adsorbent, zinc oxide photoanode) were used to improve the cell performance. Various physical measurements, including UV–vis absorption spectroscopy, electrochemical impedance spectroscopy (EIS), and incident photo–to–current conversion efficiency (IPCE) spectra, charge extraction method (CEM) and intensity-modulated photovoltage spectroscopy (IMVS) were used to obtain important parameters relevant to the cell performance for correlation between the molecular structure and the cell performance. Bipolar organic dyes containing a 9,10-dihydrophenanthrene entity in the conjugated bridge were synthesized as the sensitizers for DSSCs. The DSSC exhibits good cell efficiencies ranging from 5.21% to 5.95% under 1 sun condition. When combining the best performed dye (BP-2) with a squaraine dye (SQ2), the efficiency increment of the co-sensitized DSSCs is in compliance with the increased ratio of BP-2/SQ2. The co-sensitized DSSC in which the ratio of BP-2 and SQ2 was 8:2 (v/v) exhibited a high efficiency of 8.14%. The TiO2 film adsorbed with co-sensitizers was subjected to Auger electron spectroscopy (AES) for probing the dye distribution across the TiO2 film depth. We synthesized benzothiadiazole (BT)-containing sensitizers with BT entity directly connected to 2-cyanoacrylic acid for DSSCs using ZnO as the photoanode aiming at better charge separation because of better electron transport. The cells performed better than those using TiO2 as the photoanode. The cell efficiency can be further improved when a newly developed brush hierarchical ZnO nanoplates were used as the light back scattering layer (SL) of the cell. Dyes consisting of 2,6-conjugated anthracene segment as the conjugated spacer, 9,10-bishexyloxyanthracen-phenylamino as the electron donor, and cyanoacrylic acid as the acceptor and anchor as well were synthesized. DSSCs using these sensitizers exhibited efficiencies 4.69&;#8722;7.52% under AM 1.5 illumination, and an impressively high efficiency (9.11%) surpassing the N719-based standard cell has also been achieved with the use of CDCA co-adsorbent. In order to enhance electron injection and dark current suppression, the dyes with two anchoring groups, D-π-(A)2, were synthesized from a 2,3,5-substituted thiophene motif. These dyes exhibit high molar extinction coefficient and good power conversion efficiency of the cells. With addition of co-adsorbent, CDCA, the device performance of all the DA-based DSSCs were improved by 1.03 to 2-fold, with the best efficiency reaching 95% of the N719-based standard cell (8.28%).
9
Che-LungLee and 李喆龍. "High Efficiency of Dye-Sensitized Solar Cells Based on Ruthenium and Metal-Free Dyes." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/6jcg5e.
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Lin, Yu-Ju, and 林育如. "8H-Indeno[2,1-b]thiophene-based Metal-Free Dyes for Dye-Sensitized Solar Cells." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/5dax46.
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Hsu, Ming-Kuang, and 徐明光. "Palladium Catalysis Regioselective Benzofuran Derivative Synthesis；Novel Metal Free Organic Dyes for Dye-Sensitized Solar Cells." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/as9j8q.
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碩士國立臺北科技大學
生物科技研究所
95
This thesis consists of two parts. In the first part, as we known Benzo[b]furans are of considerable interest due to their occurrence in nature as well as their biological activities, such as anticancer、antiviral、immunosup-pressive、antioxidant、antifungal. So in the first part of the thesis, we want to investigate that benzo[b]furans accomplished in two steps：1.Sonogashira coupling reaction 2.heterannulation. The reaction is performed with a palladium catalyst, a copper(I) cocatalyst, and an amine base in organic solvent. Using the same compounds; 2-iodophenol and Methyl 3-butynoate to synthesis benzofuran derivatives. In the same reaction condition, we only change the equivalent of CuI that we can get two different compounds, 2 or 3 substitutedbenzofuran derivatives. We can get some help about the investigation of benzofuran derivatives Drug Lead in this way. The change of mankind''s life with the development of the technology and becomes more convenience and comfortable. It also makes us to need more energy. So it is very important to develop the new energy. In the second part of this thesis mainly discusses the dyestuffs part of the dye-sensitized solar cell. To date the cost of the highest efficiency of the dye-sensitized solar cell is still too high. Therefore , In order to lower costs, we developed dye-sensitized solar cell based on organic dyes. We plan to develop the new-type organic dyes. We try to modify the known dyestuffs slightly, enable dyestuffs to apply to the dye-sensitized solar cell. The known compound chromeno[3’,2’:3,4]pyrido[1,2a][1,3]benzimidazole chromophore was a relatively long-wavelength fluorophore and easily prepared in two steps. Up till now this chemical compound has not been used on the dye-sensitized solar cell. We will incorporate a carboxylic-acid group in this compound to make sure it can bind strongly to TiO2.
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黃建憲. "Dynamics of Metal-Free Organic Dyes under Various Conditions and their Applications in Dye-Sensitized Solar Cells." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/21668247539225281751.
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碩士國立交通大學
應用化學系碩博士班
100
We studied a series of organic dye, named OD0, OD1 and OD2 for their applications in dye-sensitized solar cells (DSSC). The structural between OD0, OD1 and OD2 are the peripheral derivations thiophene which contain of benzene on the diphenylamino group. In present study, the results show larger dyes with higher efficiencies. In addition, the device made of OD2 has a large open-circuit voltage (VOC > 0.8 V) similar to that of a Ru complex dye. In this study, we focused on understanding of the fundamental properties of the organic dye, and studying how the structure of the dye influenced the efficiency of DSSC. The results show that the dyes with larger size could help to improve the performance efficiency due to less aggregation and charge recombination. The results also show when OD2 was absorbed on TiO2, upward shift of the TiO2 conduction band, so as to gain a large open-circuit voltage. Longer electron lifetime and a lower injection yield was also observed of OD2. A dipole-moment was provided to explain the observed photovoltaic properties of the metal-free organic dye.
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Guo, Yi-Lin, and 郭怡凌. "Metal Free Di-anchored Organic Dyes Containing Tetraphenylethylene Moiety in the Phenothiazine Core for Dye Sensitized Solar Cells (DSSCs)." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/73fytc.
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碩士國立中央大學
化學學系
106
A series of new di-anchored organic dyes containing a tetraphenylethylene tethered phenothiazine core (YL) featuring with different π-bridging units (thiophene, 3-hexylthiophene, 4-hexyl-2, 2’-thiophene, cyclopenta[1,2-b:5,4-b']dithiophene) have been synthesized via Stille coupling, Vilsmeier-Haack formylation and Knoevenagel condensation reactions, and used as the sensitizers of dye-sensitized solar cells (DSSCs). Incorporation of a nonplanar TPE entity with propeller-like configuration is beneficial to suppressing π‒π aggregation of the dye molecules. Besides, TPE-induced more compact dye packing on TiO2 surface in collaboration with double anchors are expected to more effectively suppress the dark current of DSSCs. These new dyes have electronic absorption raging from 300 to 600 nm, with the highest molar coefficient surpassing 70000 M-1cm-1. The HOMO (5.37 to 5.47 eV) and LUMO (3.26 to 3.31) energy levels of the dyes calculated from the electrochemical and photochemical data assure sufficient thermodynamic driving force for electron ejection and regeneration. The light to electricity conversion efficiency of YL dyes ranges from 3.94 to 7.11% under simulated AM 1.5 G illuminations and from 8.64 to 11.45% under 6000 lux. Among them, the YL-2 which a 3-hexylthiophene spacer in the π-conjugated bridgunites between the donor and the acceptor has the best efficiency under 1 sun, reaching 81% of N719-based standard cell.
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Chang, Yu-Ching, and 張鈺靖. "Nitrogen/sulfur-codoped graphene hollow nanoballs as efficient metal-free electro-catalysts for dye-sensitized solar cells." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/8g7k4g.
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碩士國立臺灣大學
化學研究所
106
A huge amount of fossil fuels, such as coal, petroleum, and gas, has been consumed in order to meet the high demand of energy in the world. However, the combustion of these fossil fuels results in not only detrimentally environmental pollution, but also the rapid reduction of fossil resources on the Earth. Recently, several kinds of renewable energy, e.g., fuel cells, wind power, and solar energy, have drawn tremendous attention in academic studies and industrial applications. Among them, solar energy is the most attractive renewable energy; in particular, dye-sensitized solar cells (DSSCs) have the advantages of simple fabrication processes, low cost, flexibility, and semi-transparency. However, if a DSSC possesses low power conversion efficiency and utilizes noble metals, e.g., platinum (Pt) or ruthenium (Ru), as a counter electrode (CE), these disadvantages would hinder this DSSC from wide applications. Therefore, it is an urgent challenge to develop a noble metal-free CE with high power conversion efficiency in DSSCs. Graphene has high carrier mobility, high electrical conductivity, high mechanical strength and flexiblility. In this study, we took advantage of the unique chracteristics of graphene to fabricate high-performance DSSCs by employing different graphene-based CEs, such as graphene hollow nanoballs (GHBs), nitrogen-doped graphene hollow nanoballs (N-GHBs), sulfur-doped graphene hollow nanoballs (S-GHBs), and nitrogen/sulfur-codoped graphene hollow nanoballs (N,S-GHBs). First, we synthesized GHBs on silicon wafers (Si) or carbon cloth (CC) substrates with a chemical vapor deposition (CVD) method. A nitrogen or sulfur precursor, or both, was incorporated in the CVD rection to from N-GHBs, S-GHBs, and N,S-GHBs, respectively. Second, the as-synthesized doped GHBs were used as metal-free CEs to investigate their power conversion efficiencies in DSSCs. The highly curved GHBs could avoid the self-assembly restacking of planar graphene sheets and provide high surface area. In addition, the heteroatomic incorporation in GHBs can reduce the charge-transfer resistance and enhance the catalytic activity of GHBs. We found that pristine GHB (with ∆EP of 698 mV) and heteroatom-doped GHBs (∆EP of 530 mV for N-GHBs and ∆EP of 498 mV for S-GHBs) have different catalytic activities on the I-/I3- reduction reaction and the N,S-GHBs (∆EP of 459 mV) shows the best catalytic performance due to the synergistic effect of electronic and geometric changes. Consequently, the power conversion efficiency of a DSSC with N,S-GHBs as a CE reaches to 9.02 %, comparable to that (8.90 %) of a standard sputtered Pt CE-based cell.
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Desta, Mulu Berhe, and 徳沐露. "MOLECULAR ENGINEERING OF MONO AND DI -ANCHORING METAL FREE ORGANIC SENSITIZERS CONTAINING ELECTRON DEFICIENT ENTITY FOR DYE SENSITIZED SOLAR CELLS (DSSCs)." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/f6d5f5.
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博士國立交通大學
永續化學科技國際研究生博士學位學程
106
The growth of global population and rising energy demand, coupled with environmental concerns, as well as the depletion of non-renewable petroleum resources have motivated researchers to seek alternative, environmentally friendly low-carbon renewable energy sources, such as solar energy. From the past few years, di-anchoring metal-free organic dyes (i.e. D‒ (π‒A)2) had attracted an immense potential due to better light harvesting (and therefore higher photocurrent) compared with their mono-anchoring congeners, due to better conjugation and/or higher dye loading. In this thesis, we have targeted the design, synthesis and characterization of several organic dyes bearing mono/di-anchoring groups. The synthesis of the organic dyes was based on our novel approach D‒A'‒π‒A for mono-anchoring and D‒ (π‒A)2 for di-anchoring dyes, where A' refers to electron deficient entities, D refers to Donor and A refers to electron acceptor/anchoring group (i. e. cyanoacetic acid). In our first project we started working on benzimidazole based di-anchoring compounds, we prepared three new dyes MD1–MD3, the overall performance of the DSSCs prepared showed better efficiencies ranging between 4.74‒6.69%, compared to their mono-anchor congeners and other reported dyes. Since these dyes shows a blue shifted absorption, another interesting electron deficient entity pyrazine was chosen as a building block. In the second project, we intended to develop metal-free sensitizers for both indoor and outdoor DSSCs. We figured that dyes with panchromatic absorption in the visible region up to ~650 nm could cover the spectrum of T5 or white LED light source. In order to achieve this goal, we set out to develop D−A′−π−A type sensitizers. Incorporation of an electron deficient entity as auxiliary acceptor in the conjugated spacer of D−π−A dyes is beneficial for red shifting the absorption spectra due to deepened LUMO and improving the photostability of sensitizers. New D−A′−π−A type sensitizers with two bis(alkoxy)phenyl substituents incorporated thieno[3,4-b]pyrazines (TP) or benzo[3,4-b]pyrazine (BP) entity as the auxiliary acceptor have been synthesized for dye-sensitized solar cells (DSSCs) application. Under 1 sun illumination, the DSSCs fabricated from the two BP dyes with co-adsorbent have efficiencies of 8.39% and 9.03%, respectively. The latter surpasses that of the standard N719 dye (8.87%). Under dim light condition MD7 exhibited a power conversion efficiency of 18.95% and 27.17% under 300 lux and 6000 lux irradiance, respectively.
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Li, Wei-Ming, and 李偉銘. "Combining C-H/C-Br and C-H/C-H Direct Arylations: An Efficient Synthetic Tool for the Study of Internal Aceeptor Effect on PCE of Metal-Free Dye Sensitizers." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/40974964668206745196.
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碩士國立中央大學
化學工程與材料工程學系
105
Rapid preparation of organic dye by efficient synthetic method C-H arylation and cross-dehydrogenative coupling, we synthesizing four new sensitizers (CYL-14~CYL-17) were prepared and employed to fabricate DSSCs devices affords a Voc of 0.58-0.65 V, a Jsc of 4.91-8.29 mA/cm2, and a FF of 68.8-74.1 %, which correspond to an overall power conversion efficiency of 2.25-4.85 %. Obtain the auxiliary electron acceptor adjacent to the electron donor is the best, so our synthesizing two new sensitizers (CYL-18、CYL-19) were prepared and employed to fabricate DSSCs devices affords a Voc of 0.70-0.79 V, a Jsc of 10.43-13.74 mA/cm2, and a FF of 68.29-70.86 %, which correspond to an overall power conversion efficiency of 5.14-7.17 %. Among them, CYL-18 efficiency is up to 7.17 %, which is higher than the commercially available dye Z907 (PCE = 7.04 %).