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Jianyong Ouyang - One of the best experts on this subject based on the ideXlab platform.
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efficiency enhancement of planar perovskite solar cells by adding Zwitterion lif double interlayers for electron collection
Nanoscale, 2015Co-Authors: Kuan Sun, Jingjing Chang, Furkan Halis Isikgor, Jianyong OuyangAbstract:Double interlayers consisting of a Zwitterionic small molecule layer and a LiF layer were introduced between the electron transport layer and the cathode of perovskite solar cells. The double interlayers improve the photovoltaic efficiency to 13.2%, which is higher than that of control devices without the double interlayer (9.2%) or with LiF (11.0%) or rhodamine 101 Zwitterion (12.1%) alone.
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highly efficient inverted polymer solar cells with indium tin oxide modified with solution processed Zwitterions as the transparent cathode
ACS Applied Materials & Interfaces, 2012Co-Authors: Baomin Zhao, Amit Kumar, Kaiyang Zeng, Jianyong OuyangAbstract:Polymer solar cells (PSCs) with inverted structure can greatly improve photovoltaic stability. This paper reports a novel method to lower the work function of indium tin oxide (ITO) through the modification with a thin layer of Zwitterions which have both positive and negative charges in the same molecule. Zwitterions have a strong dipole moment due to the presence of the two types of charges and are immobile under electric field. Zwitterions with both conjugated and saturated structure were investigated. A Zwitterion thin layer is formed on ITO by spin coating a methanol solution of the Zwitterion. The Zwitterion-modified ITO sheets can be used as the cathode for the electron collection of inverted PSCs. The inverted poly(3-hexylthiophene):[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PC(61)BM) PSCs can exhibit photovoltaic efficiency as high as 3.98% under simulated AM1.5G illumination (100 mW cm(-2)), which is comparable to that of PSCs with normal architecture. The effective electron collection by the Zwitterion-modified ITO sheets is attributed to the reduction of the work function of ITO as a result of the dipole moment by the Zwitterions. The Zwitterion modification can lower the work function of ITO by up to 0.97 eV. The photovoltaic performance of PSCs and the reduction in the work function of ITO strongly depend on the chemical structure of the Zwitterions.
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highly efficient inverted polymer solar cells with indium tin oxide modified with solution processed Zwitterions as the transparent cathode
ACS Applied Materials & Interfaces, 2012Co-Authors: Baomin Zhao, Amit Kumar, Kaiyang Zeng, Jianyong OuyangAbstract:Polymer solar cells (PSCs) with inverted structure can greatly improve photovoltaic stability. This paper reports a novel method to lower the work function of indium tin oxide (ITO) through the modification with a thin layer of Zwitterions which have both positive and negative charges in the same molecule. Zwitterions have a strong dipole moment due to the presence of the two types of charges and are immobile under electric field. Zwitterions with both conjugated and saturated structure were investigated. A Zwitterion thin layer is formed on ITO by spin coating a methanol solution of the Zwitterion. The Zwitterion-modified ITO sheets can be used as the cathode for the electron collection of inverted PSCs. The inverted poly(3-hexylthiophene):[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PC61BM) PSCs can exhibit photovoltaic efficiency as high as 3.98% under simulated AM1.5G illumination (100 mW cm–2), which is comparable to that of PSCs with normal architecture. The effective electron collection by the ...
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highly conductive pedot pss films prepared through a treatment with Zwitterions and their application in polymer photovoltaic cells
Journal of Materials Chemistry, 2010Co-Authors: Hongmei Zhang, Jianyong OuyangAbstract:This paper reports the significant conductivity enhancement of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films through a treatment with aqueous solutions of Zwitterions for the first time. The conductivity enhancement was dependent on the structure of the Zwitterions and the experimental conditions during the treatment, such as the concentration of the Zwitterions and the temperature. Conductivity enhancement from 0.2 to 92.4 S cm−1 was observed on PEDOT:PSS films after a Zwitterion treatment. The chemical and physical characterizations indicate the lowering of the energy barrier for charge hopping across the PEDOT chains, the loss of poly(styrene sulfonate) acid (PSSH) chains from the PEDOT:PSS film, and the conformational change of the PEDOT chains after the Zwitterion treatment. These highly conductive PEDOT:PSS films could be used to replace indium tin oxide (ITO) as the transparent anode of polymer photovoltaic cells (PVs). Power conversion efficiency as high as 2.48% was observed on the polymer PVs with a Zwitterion-treated PEDOT:PSS film as the transparent anode.
Baomin Zhao - One of the best experts on this subject based on the ideXlab platform.
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highly efficient inverted polymer solar cells with indium tin oxide modified with solution processed Zwitterions as the transparent cathode
ACS Applied Materials & Interfaces, 2012Co-Authors: Baomin Zhao, Amit Kumar, Kaiyang Zeng, Jianyong OuyangAbstract:Polymer solar cells (PSCs) with inverted structure can greatly improve photovoltaic stability. This paper reports a novel method to lower the work function of indium tin oxide (ITO) through the modification with a thin layer of Zwitterions which have both positive and negative charges in the same molecule. Zwitterions have a strong dipole moment due to the presence of the two types of charges and are immobile under electric field. Zwitterions with both conjugated and saturated structure were investigated. A Zwitterion thin layer is formed on ITO by spin coating a methanol solution of the Zwitterion. The Zwitterion-modified ITO sheets can be used as the cathode for the electron collection of inverted PSCs. The inverted poly(3-hexylthiophene):[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PC(61)BM) PSCs can exhibit photovoltaic efficiency as high as 3.98% under simulated AM1.5G illumination (100 mW cm(-2)), which is comparable to that of PSCs with normal architecture. The effective electron collection by the Zwitterion-modified ITO sheets is attributed to the reduction of the work function of ITO as a result of the dipole moment by the Zwitterions. The Zwitterion modification can lower the work function of ITO by up to 0.97 eV. The photovoltaic performance of PSCs and the reduction in the work function of ITO strongly depend on the chemical structure of the Zwitterions.
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highly efficient inverted polymer solar cells with indium tin oxide modified with solution processed Zwitterions as the transparent cathode
ACS Applied Materials & Interfaces, 2012Co-Authors: Baomin Zhao, Amit Kumar, Kaiyang Zeng, Jianyong OuyangAbstract:Polymer solar cells (PSCs) with inverted structure can greatly improve photovoltaic stability. This paper reports a novel method to lower the work function of indium tin oxide (ITO) through the modification with a thin layer of Zwitterions which have both positive and negative charges in the same molecule. Zwitterions have a strong dipole moment due to the presence of the two types of charges and are immobile under electric field. Zwitterions with both conjugated and saturated structure were investigated. A Zwitterion thin layer is formed on ITO by spin coating a methanol solution of the Zwitterion. The Zwitterion-modified ITO sheets can be used as the cathode for the electron collection of inverted PSCs. The inverted poly(3-hexylthiophene):[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PC61BM) PSCs can exhibit photovoltaic efficiency as high as 3.98% under simulated AM1.5G illumination (100 mW cm–2), which is comparable to that of PSCs with normal architecture. The effective electron collection by the ...
Paitoon Tontiwachwuthikul - One of the best experts on this subject based on the ideXlab platform.
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Supplementary materials A the rate equation development from Eley–Rideal model of heterogeneous catalytic carbamate formation based on CO2–MEA absorptions with CaCO3, MgCO3 and BaCO3
2019Co-Authors: Huancong Shi, Min Huang, Yuandong Huang, Lifeng Cui, Linna Zheng, Mingqi Cui, Linhua Jiang, Hussameldin Ibrahim, Paitoon TontiwachwuthikulAbstract:The mechanism was proposed of heterogeneous catalytic CO2 absorptions with primary/secondary amines involving ‘catalytic carbamate formation’. Compared with the non-catalytic ‘Zwitterion mechanism’, this Eley–Rideal model was proposed for CO2 + RR′NH with MCO3 (M = Ca, Mg, and Ba) with four elementary reaction steps: (B1) amine adsorption, (B2) Zwitterion formation, (B3) carbamate formation, and (B4) carbamate desorption. The rate law if determining step of each elementary step was generated based on ‘steady-state approximation’. Furthermore, the solid chemicals were characterized by SEM and BET, and this rate model was verified with 39 sets of experimental datasets of catalytic CO2–MEA absorptions with the existence of 0–25 g CaCO3, MgCO3 and BaCO3. The results indicated that the rate-determining step was B1 as amine adsorption onto solid surface, which was pseudo-1st-order for MEA. This was the first time that the Eley–Rideal model had been adopted onto the reactions of CO2 + primary/secondary amines over alkaline earth metal carbonate (MCO3)
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Supplementary materials B the experimental data from Eley–Rideal model of heterogeneous catalytic carbamate formation based on CO2–MEA absorptions with CaCO3, MgCO3 and BaCO3
2019Co-Authors: Huancong Shi, Min Huang, Yuandong Huang, Lifeng Cui, Linna Zheng, Mingqi Cui, Linhua Jiang, Hussameldin Ibrahim, Paitoon TontiwachwuthikulAbstract:The mechanism was proposed of heterogeneous catalytic CO2 absorptions with primary/secondary amines involving ‘catalytic carbamate formation’. Compared with the non-catalytic ‘Zwitterion mechanism’, this Eley–Rideal model was proposed for CO2 + RR′NH with MCO3 (M = Ca, Mg, and Ba) with four elementary reaction steps: (B1) amine adsorption, (B2) Zwitterion formation, (B3) carbamate formation, and (B4) carbamate desorption. The rate law if determining step of each elementary step was generated based on ‘steady-state approximation’. Furthermore, the solid chemicals were characterized by SEM and BET, and this rate model was verified with 39 sets of experimental datasets of catalytic CO2–MEA absorptions with the existence of 0–25 g CaCO3, MgCO3 and BaCO3. The results indicated that the rate-determining step was B1 as amine adsorption onto solid surface, which was pseudo-1st-order for MEA. This was the first time that the Eley–Rideal model had been adopted onto the reactions of CO2 + primary/secondary amines over alkaline earth metal carbonate (MCO3)
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reaction kinetics of co2 in aqueous 1 amino 2 propanol 3 amino 1 propanol and dimethylmonoethanolamine solutions in the temperature range of 298 313 k using the stopped flow technique
Industrial & Engineering Chemistry Research, 2008Co-Authors: Amr Henni, Juelin Li, Paitoon TontiwachwuthikulAbstract:The observed pseudo-first-order rate constants (ko) for the reactions between CO2 and 1-amino-2-propanol (1-AP), 3-amino-1-propanol (3-AP), and dimethylmonoethanolamine (DMMEA) have been measured using the stopped-flow technique in aqueous solutions at 298, 303, 308, and 313 K. The alkanolamine concentrations ranged from 25.3 to 82.0 mol·m-3 for 1-AP, 27.0 to 60.7 mol·m-3 for 3-AP, and 304.0 to 984.8 mol·m-3 for DMMEA. The Zwitterion mechanism was used to correlate the experimentally obtained rate constants. Both the Zwitterion formation step and the proton-removal step played a significant role for 1-AP and 3-AP. The reaction rate of CO2 in the aqueous-3-AP solution was found to be faster than that in aqueous monoethanolamine (MEA). The absorption rate of CO2 in the latter was faster than that in aqueous 1-AP solution under the conditions studied. The reaction rate of CO2 in DMMEA was higher than that in methyldiethanolamine (MDEA) but not in diethyl-monoethanolamine (DEMEA). The base catalysis of the CO...
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reaction kinetics of co2 in aqueous ethylenediamine ethyl ethanolamine and diethyl monoethanolamine solutions in the temperature range of 298 313 k using the stopped flow technique
Industrial & Engineering Chemistry Research, 2008Co-Authors: Juelin Li, Amr Henni, Paitoon TontiwachwuthikulAbstract:The observed pseudo-first-order rate constants (k0) for the reactions between CO2 and ethylenediamine (EDA), ethyl ethanolamine (EEA), and diethyl monoethanolamine (DEMEA) have been studied using the stopped-flow technique in an aqueous solution at 298, 303, 308, and 313 K. The amine concentrations ranged from 26.2 mol/m3 to 67.6 mol/m3 for EDA, 28.2 mol/m3 to 81.9 mol/m3 for EEA, and 196.5 mol/m3 to 997.4 mol/m3 for DEMEA. The Zwitterion mechanism was used to correlate the experimentally obtained rate constants. Both the Zwitterion formation step and the proton removal step had a significant role for the primary and secondary amines (EDA and EEA). The reaction rate of CO2 in an aqueous EDA solution was observed to be much faster than that in aqueous MEA solution. The rate in aqueous EEA was much faster than in aqueous DEA, under the conditions studied. Finally, the reaction rate constant of CO2 in an aqueous tertiary amine (DEMEA) solution was observed to be much faster than that in methyl diethanolamine...
Carsten Schmuck - One of the best experts on this subject based on the ideXlab platform.
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a new type of soft vesicle forming molecule an amino acid derived guanidiniocarbonyl pyrrole carboxylate Zwitterion
Organic Letters, 2008Co-Authors: Thomas H Rehm, Vladimir Stepanenko, Xin Zhang, Frank Wurthner, Franziska Grohn, Katja Klein, Carsten SchmuckAbstract:The self-assembly of the l-alanine derived Zwitterion 3 leads to the formation of soft vesicles in solution even though this surprisingly small molecule does not possess the classical amphiphilic features of other vesicle-forming monomers.
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ion pair driven self assembly of a flexible bis Zwitterion in polar solution formation of discrete nanometer sized cyclic dimers
Journal of the American Chemical Society, 2006Co-Authors: Carsten Schmuck, Thomas H Rehm, Franziska Grohn, Katja Klein, Frank ReinholdAbstract:The self-complementary flexible bis-Zwitterion 1 forms discrete nanometer-sized cyclic dimers via ion pair driven self-assembly even in polar solvents. The existence of such dimers was confirmed by DOSY NMR, FAB-MS, and scattering experiments (DLS, SANS) which all indicate the concentration-dependent formation of cyclic dimers with a hydrodynamic radius of rH ≈ 2.5 nm in solution.
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ion pair driven self assembly of a flexible bis Zwitterion in polar solution formation of discrete nanometer sized cyclic dimers
Journal of the American Chemical Society, 2006Co-Authors: Carsten Schmuck, Thomas H Rehm, Franziska Grohn, Katja Klein, Frank ReinholdAbstract:The self-complementary flexible bis-Zwitterion 1 forms discrete nanometer-sized cyclic dimers via ion pair driven self-assembly even in polar solvents. The existence of such dimers was confirmed by DOSY NMR, FAB-MS, and scattering experiments (DLS, SANS) which all indicate the concentration-dependent formation of cyclic dimers with a hydrodynamic radius of rH approximately 2.5 nm in solution.
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highly stable self assembly in water ion pair driven dimerization of a guanidiniocarbonyl pyrrole carboxylate Zwitterion
Journal of the American Chemical Society, 2003Co-Authors: Carsten Schmuck, Wolfgang WienandAbstract:The synthesis of a novel water-soluble guanidiniocarbonyl pyrrole carboxylate Zwitterion 2 is described, and its self-association in aqueous solutions is studied. Zwitterion 2 forms extremely stable 1:1 dimers which are held together by an extensive hydrogen bonding network in combination with two mutual interacting ion pairs as could be shown by ESI MS and X-ray structure determination. NMR dilution studies in different highly polar solvents showed that dimerization is fast on the NMR time scale with association constants ranging from an estimated 1010 M-1 in DMSO to a surprisingly high 170 M-1 in water. Hence, Zwitterion 2 belongs to the most efficient self-assembling systems solely on the basis of electrostatic interactions reported so far. Furthermore, an amidopyridine pyrrole carboxylic acid 10 was developed as a neutral analogue of Zwitterion 2, which also dimerizes with an essentially identical hydrogen bonding pattern (according to ESI MS and X-ray structure determination) but lacking the ionic in...
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highly stable self assembly in water ion pair driven dimerization of a guanidiniocarbonyl pyrrole carboxylate Zwitterion
Journal of the American Chemical Society, 2003Co-Authors: Carsten Schmuck, Wolfgang WienandAbstract:The synthesis of a novel water-soluble guanidiniocarbonyl pyrrole carboxylate Zwitterion 2 is described, and its self-association in aqueous solutions is studied. Zwitterion 2 forms extremely stable 1:1 dimers which are held together by an extensive hydrogen bonding network in combination with two mutual interacting ion pairs as could be shown by ESI MS and X-ray structure determination. NMR dilution studies in different highly polar solvents showed that dimerization is fast on the NMR time scale with association constants ranging from an estimated 10(10) M(-1) in DMSO to a surprisingly high 170 M(-1) in water. Hence, Zwitterion 2 belongs to the most efficient self-assembling systems solely on the basis of electrostatic interactions reported so far. Furthermore, an amidopyridine pyrrole carboxylic acid 10 was developed as a neutral analogue of Zwitterion 2, which also dimerizes with an essentially identical hydrogen bonding pattern (according to ESI MS and X-ray structure determination) but lacking the ionic interactions. NMR binding studies demonstrated that the solely hydrogen-bonded neutral dimer of 10 is stable only in organic solvents of low polarity (K > 10(4) M(-1) in CDCl3 but <10 M(-1) in 5% DMSO in CDCl3). The comparison of both systems impressively underlines the importance of ion pair interactions for stable self-association of such H-bonded binding motifs in water.
Amit Kumar - One of the best experts on this subject based on the ideXlab platform.
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highly efficient inverted polymer solar cells with indium tin oxide modified with solution processed Zwitterions as the transparent cathode
ACS Applied Materials & Interfaces, 2012Co-Authors: Baomin Zhao, Amit Kumar, Kaiyang Zeng, Jianyong OuyangAbstract:Polymer solar cells (PSCs) with inverted structure can greatly improve photovoltaic stability. This paper reports a novel method to lower the work function of indium tin oxide (ITO) through the modification with a thin layer of Zwitterions which have both positive and negative charges in the same molecule. Zwitterions have a strong dipole moment due to the presence of the two types of charges and are immobile under electric field. Zwitterions with both conjugated and saturated structure were investigated. A Zwitterion thin layer is formed on ITO by spin coating a methanol solution of the Zwitterion. The Zwitterion-modified ITO sheets can be used as the cathode for the electron collection of inverted PSCs. The inverted poly(3-hexylthiophene):[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PC(61)BM) PSCs can exhibit photovoltaic efficiency as high as 3.98% under simulated AM1.5G illumination (100 mW cm(-2)), which is comparable to that of PSCs with normal architecture. The effective electron collection by the Zwitterion-modified ITO sheets is attributed to the reduction of the work function of ITO as a result of the dipole moment by the Zwitterions. The Zwitterion modification can lower the work function of ITO by up to 0.97 eV. The photovoltaic performance of PSCs and the reduction in the work function of ITO strongly depend on the chemical structure of the Zwitterions.
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highly efficient inverted polymer solar cells with indium tin oxide modified with solution processed Zwitterions as the transparent cathode
ACS Applied Materials & Interfaces, 2012Co-Authors: Baomin Zhao, Amit Kumar, Kaiyang Zeng, Jianyong OuyangAbstract:Polymer solar cells (PSCs) with inverted structure can greatly improve photovoltaic stability. This paper reports a novel method to lower the work function of indium tin oxide (ITO) through the modification with a thin layer of Zwitterions which have both positive and negative charges in the same molecule. Zwitterions have a strong dipole moment due to the presence of the two types of charges and are immobile under electric field. Zwitterions with both conjugated and saturated structure were investigated. A Zwitterion thin layer is formed on ITO by spin coating a methanol solution of the Zwitterion. The Zwitterion-modified ITO sheets can be used as the cathode for the electron collection of inverted PSCs. The inverted poly(3-hexylthiophene):[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PC61BM) PSCs can exhibit photovoltaic efficiency as high as 3.98% under simulated AM1.5G illumination (100 mW cm–2), which is comparable to that of PSCs with normal architecture. The effective electron collection by the ...
