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Tianshou Zhao - One of the best experts on this subject based on the ideXlab platform.
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Transport phenomena in alkaline direct Ethanol Fuel cells for sustainable energy production
Journal of Power Sources, 2017Co-Authors: Liang An, Tianshou ZhaoAbstract:Abstract Alkaline direct Ethanol Fuel cells (DEFC), which convert the chemical energy stored in Ethanol directly into electricity, are one of the most promising energy-conversion devices for portable, mobile and stationary power applications, primarily because this type of Fuel cell runs on a carbon-neutral, sustainable Fuel and the electrocatalytic and membrane materials that constitute the cell are relatively inexpensive. As a result, the alkaline DEFC technology has undergone a rapid progress over the last decade. This article provides a comprehensive review of transport phenomena of various species in this Fuel cell system. The past investigations into how the design and structural parameters of membrane electrode assemblies and the operating parameters affect the Fuel cell performance are discussed. In addition, future perspectives and challenges with regard to transport phenomena in this Fuel cell system are also highlighted.
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Carbon-neutral sustainable energy technology: Direct Ethanol Fuel cells
Renewable & Sustainable Energy Reviews, 2015Co-Authors: Liang An, Tianshou Zhao, Yinshi LiAbstract:Ethanol is a sustainable, carbon-neutral transportation Fuel. It is an ideal Fuel source for direct oxidation Fuel cells for portable and mobile applications, as it offers multiple advantages over hydrogen and mEthanol, including ease of transportation, storage and handling as well as higher energy density. Tremendous efforts have been made to improve direct Ethanol Fuel cells (DEFC) that use proton exchange membranes. This type of acid DEFC still exhibits low performance (the state-of-the-art peak power density is 96mWcm−2 at 90°C), despite employing expensive platinum-based catalysts. However, it has been recently demonstrated that the use of anion exchange membranes and non-platinum catalysts in DEFCs enables a dramatic boost in performance (the state-of-the-art peak power density can be as high as 185mWcm−2 at 60°C). This article provides an overview of both acid and alkaline DEFC technologies by describing their working principles, cell performance, system efficiency, products of the Ethanol oxidation reaction, and cost. Recent innovations and future perspectives of alkaline DEFCs are particularly emphasized.
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performance of an alkaline direct Ethanol Fuel cell with hydrogen peroxide as oxidant
International Journal of Hydrogen Energy, 2014Co-Authors: Liang A, Tianshou Zhao, Li ZengAbstract:An alkaline direct Ethanol Fuel cell (DEFC) with hydrogen peroxide as the oxidant is developed and tested. The present Fuel cell consists of a non-platinum anode, an anion exchange membrane, and a non-platinum cathode. It is demonstrated that the peak power density of the Fuel cell is 130 mW cm � 2 at 60 � C (160 mW cm � 2 at 80 � C), which is 44% higher than that of the same Fuel cell setup but with oxygen as the oxidant. The improved performance as compared with the Fuel cell with oxygen as the oxidant is mainly attributed to the superior electrochemical kinetics of the hydrogen peroxide reduction reaction and the reduced ohmic loss associated with the liquid oxidant.
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synthesis and characterization of crosslinked poly vinyl alcohol layered double hydroxide composite polymer membranes for alkaline direct Ethanol Fuel cells
International Journal of Hydrogen Energy, 2012Co-Authors: Lin Zeng, Tianshou ZhaoAbstract:The low ionic conductivity and low thermal stability of conventional quaternary ammonium group functionalized anion-exchange membranes (AEM) are two key parameters that limit the performance of AEM direct Ethanol Fuel cells (AEM DEFCs). The present work is to address these issues by synthesizing crosslinked poly (vinyl alcohol)/layered double hydroxide (PVA/LDH) hybrid membranes with solution casting method. The experimental results indicate that incorporating 20 wt.% LDH into the PVA resulted in not only a higher ionic conductivity, but also a lower Ethanol permeability. The performance test of the DEFC using the PVA/LDH hybrid membrane shows that the Fuel cell can yield a power density of 82 mW cm � 2 at 80 � C, which is much higher than that of the AEM DEFC employing the
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performance of an alkaline acid direct Ethanol Fuel cell
International Journal of Hydrogen Energy, 2011Co-Authors: Liang A, Tianshou ZhaoAbstract:Abstract This paper reports on the performance of an alkaline-acid direct Ethanol Fuel cell (AA-DEFC) that is composed of an alkaline anode, a membrane and an acid cathode. The effects of membrane thickness and the concentrations of various species at both the anode and cathode on the cell performance are investigated. It has been demonstrated that the peak power density of this AA-DEFC that employs a 25-μm thick membrane is as high as 360 mW cm−2 at 60 °C, which is about 6 times higher than the performance of conventional DEFCs reported in the literature.
Liang Hong - One of the best experts on this subject based on the ideXlab platform.
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membrane design for direct Ethanol Fuel cells a hybrid proton conducting interpenetrating polymer network
Fuel Cells, 2008Co-Authors: Rong Qiang Fu, Liang HongAbstract:A series of hybrid proton-conducting membranes with an interpenetrating polymer network (IPN) structure was designed with the direct Ethanol Fuel cell (DEFC) application in mind. In these membranes, glutaraldehyde crosslinked poly(vinyl alcohol) (PVA) were interpenetrated with the copolymer of 2-acrylamido-2-methyl-propanesulphonic acid (AMPS) and 2-hydroxyethyl methacrylate (HEMA) crosslinked by poly(ethylene glycol) dimethacrylate (PEGDMA). Silica from the in situ sol–gel hydrolysis of tetraethyl orthosilicate (TEOS) was uniformly dispersed in the polymer matrix. The membranes fabricated as such had ion exchange capacities of 0.84–1.43 meq g–1 and proton conductivities of 0.02–0.11 S cm–1. The membranes exhibited significantly lower Fuel permeabilities than that of Nafion. In a manner totally unlike Nafion, Fuel permeabilities were lower at higher Fuel concentrations, and were lower in Ethanol than mEthanol solutions. These behaviours are all relatable to the unique swelling characteristics of PVA (no swelling in Ethanol, partial swelling in mEthanol and extensive swelling in water) and to the Fuel blocking and swelling suppression properties of silica particles. The membranes are promising for DEFC applications since a high concentration of Fuel may be used to reduce Fuel crossover and to improve the anode kinetics for a resultant increase in both the energy and power densities of the Fuel cell.
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membrane design for direct Ethanol Fuel cells a hybrid proton conducting interpenetrating polymer network
Fuel Cells, 2008Co-Authors: Rong Qiang Fu, Liang HongAbstract:A series of hybrid proton-conducting membranes with an interpenetrating polymer network (IPN) structure was designed with the direct Ethanol Fuel cell (DEFC) application in mind. In these membranes, glutaraldehyde crosslinked poly(vinyl alcohol) (PVA) were interpenetrated with the copolymer of 2-acrylamido-2-methyl-propanesulphonic acid (AMPS) and 2-hydroxyethyl methacrylate (HEMA) crosslinked by poly(ethylene glycol) dimethacrylate (PEGDMA). Silica from the in situ sol–gel hydrolysis of tetraethyl orthosilicate (TEOS) was uniformly dispersed in the polymer matrix. The membranes fabricated as such had ion exchange capacities of 0.84–1.43 meq g–1 and proton conductivities of 0.02–0.11 S cm–1. The membranes exhibited significantly lower Fuel permeabilities than that of Nafion. In a manner totally unlike Nafion, Fuel permeabilities were lower at higher Fuel concentrations, and were lower in Ethanol than mEthanol solutions. These behaviours are all relatable to the unique swelling characteristics of PVA (no swelling in Ethanol, partial swelling in mEthanol and extensive swelling in water) and to the Fuel blocking and swelling suppression properties of silica particles. The membranes are promising for DEFC applications since a high concentration of Fuel may be used to reduce Fuel crossover and to improve the anode kinetics for a resultant increase in both the energy and power densities of the Fuel cell.
Panagiotis Tsiakaras - One of the best experts on this subject based on the ideXlab platform.
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direct Ethanol Fuel cells based on ptsn anodes the effect of sn content on the Fuel cell performance
Journal of Power Sources, 2005Co-Authors: Weijiang Zhou, Shuqin Song, S. Douvartzides, Qin Xin, Z.-h. Zhou, Gongquan Sun, Panagiotis TsiakarasAbstract:Abstract In the present work, several carbon supported PtSn catalysts with different Pt/Sn atomic ratios were synthesized and characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Both the results of TEM and XRD showed that all in-house prepared carbon supported Pt and PtSn catalysts had nanosized particles with narrow size distribution. According to the primary analysis of XPS results, it was confirmed that the main part of Pt of the as-prepared catalysts is in metallic state while the main part of Sn is in oxidized state. The performances of single direct Ethanol Fuel cells were different from each other with different anode catalysts and at different temperatures. It was found that, the single DEFC employing Pt3Sn2/C showed better performance at 60 °C while the direct Ethanol Fuel cells with Pt2Sn1/C and Pt3Sn2/C exhibited similar performances at 75 °C. Furthermore, at 90 °C, Pt2Sn1/C was identified as a more suitable anode catalyst for direct Ethanol Fuel cells in terms of the Fuel cell maximum power density. Surface oxygen-containing species, lattice parameters and ohmic effects, which are related to the Sn content, are thought as the main factors influencing the catalyst activity and consequently the performance of single direct Ethanol Fuel cells.
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Direct Ethanol Fuel cells based on PtSn anodes:the effect of Sn content on the Fuel cell performance
Journal of Power Sources, 2005Co-Authors: Weijiang Zhou, Shuqin Song, S. Douvartzides, Qin Xin, Z.-h. Zhou, Wenzhen Li, G-q Sun, Panagiotis TsiakarasAbstract:In the present work, several carbon supported ptsn catalysts with different pt/sn atomic ratios were synthesized and characterized by x-ray diffraction (xrd), transmission electron microscopy (tem) and x-ray photoelectron spectroscopy (xps). both the results of tem and xrd showed that all in-house prepared carbon supported pt and ptsn catalysts had nanosized particles with narrow size distribution. according to the primary analysis of xps results, it was confirmed that the main part of pt of the as-prepared catalysts is in metallic state while the main part of sn is in oxidized state. the performances of single direct Ethanol Fuel cells were different from each other with different anode catalysts and at different temperatures. it was found that, the single defc employing pt3sn2/c showed better performance at 60degreesc while the direct Ethanol Fuel cells with pt2sn1/c and pt3sn2/c exhibited similar performances at 75 degreesc. furthermore, at 90 degreesc, pt2sn1/c was identified as a more suitable anode catalyst for direct Ethanol Fuel cells in terms of the Fuel cell maximum power density. surface oxygen-containing species, lattice parameters and ohmic effects, which are related to the sn content, are thought as the main factors influencing the catalyst activity and consequently the performance of single direct Ethanol Fuel cells. (c) 2004 elsevier b.v. all rights reserved.
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Bi- and tri-metallic Pt-based anode catalysts for direct Ethanol Fuel cells
Journal of Power Sources, 2004Co-Authors: W J Zhou, S. Q. Song, K. Poulianitis, Stella Kontou, Qiang Xin, W.z Li, Z.-h. Zhou, L H Jiang, G-q Sun, Panagiotis TsiakarasAbstract:In the present work, several Pt-based anode catalysts supported on activated carbon XC-72R were prepared by using a novel method, characterized and tested. XRD analysis and TEM images indicated that all of anode catalysts consist of uniform nanosized particles with sharp distribution and that the Pt lattice parameter becomes shorter with the addition of Ru and Pd and bigger with the addition of Sn and W. Cyclic voltammetry (CV) measurements and single direct Ethanol Fuel cell (DEFC) tests jointly showed that Sn, Ru and W can enhance Ethanol electro-oxidation activity of Pt in the following order: Pt 1Sn1/C > Pt1Ru1/C > Pt 1W1/C > Pt1Pd1/C > Pt/C. The Pt1Ru1/C catalyst was modified with Mo, W and Sn, respectively. It was found that the DEFCs performances were improved with these modified Pt1Ru1/C catalysts as anode catalysts. This distinct DEFC performance behavior is attributed to the so-called bifunctional mechanism and to the electronic interaction between Pt and additives. © 2004 Elsevier B.V. All rights reserved.
Rong Qiang Fu - One of the best experts on this subject based on the ideXlab platform.
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membrane design for direct Ethanol Fuel cells a hybrid proton conducting interpenetrating polymer network
Fuel Cells, 2008Co-Authors: Rong Qiang Fu, Liang HongAbstract:A series of hybrid proton-conducting membranes with an interpenetrating polymer network (IPN) structure was designed with the direct Ethanol Fuel cell (DEFC) application in mind. In these membranes, glutaraldehyde crosslinked poly(vinyl alcohol) (PVA) were interpenetrated with the copolymer of 2-acrylamido-2-methyl-propanesulphonic acid (AMPS) and 2-hydroxyethyl methacrylate (HEMA) crosslinked by poly(ethylene glycol) dimethacrylate (PEGDMA). Silica from the in situ sol–gel hydrolysis of tetraethyl orthosilicate (TEOS) was uniformly dispersed in the polymer matrix. The membranes fabricated as such had ion exchange capacities of 0.84–1.43 meq g–1 and proton conductivities of 0.02–0.11 S cm–1. The membranes exhibited significantly lower Fuel permeabilities than that of Nafion. In a manner totally unlike Nafion, Fuel permeabilities were lower at higher Fuel concentrations, and were lower in Ethanol than mEthanol solutions. These behaviours are all relatable to the unique swelling characteristics of PVA (no swelling in Ethanol, partial swelling in mEthanol and extensive swelling in water) and to the Fuel blocking and swelling suppression properties of silica particles. The membranes are promising for DEFC applications since a high concentration of Fuel may be used to reduce Fuel crossover and to improve the anode kinetics for a resultant increase in both the energy and power densities of the Fuel cell.
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membrane design for direct Ethanol Fuel cells a hybrid proton conducting interpenetrating polymer network
Fuel Cells, 2008Co-Authors: Rong Qiang Fu, Liang HongAbstract:A series of hybrid proton-conducting membranes with an interpenetrating polymer network (IPN) structure was designed with the direct Ethanol Fuel cell (DEFC) application in mind. In these membranes, glutaraldehyde crosslinked poly(vinyl alcohol) (PVA) were interpenetrated with the copolymer of 2-acrylamido-2-methyl-propanesulphonic acid (AMPS) and 2-hydroxyethyl methacrylate (HEMA) crosslinked by poly(ethylene glycol) dimethacrylate (PEGDMA). Silica from the in situ sol–gel hydrolysis of tetraethyl orthosilicate (TEOS) was uniformly dispersed in the polymer matrix. The membranes fabricated as such had ion exchange capacities of 0.84–1.43 meq g–1 and proton conductivities of 0.02–0.11 S cm–1. The membranes exhibited significantly lower Fuel permeabilities than that of Nafion. In a manner totally unlike Nafion, Fuel permeabilities were lower at higher Fuel concentrations, and were lower in Ethanol than mEthanol solutions. These behaviours are all relatable to the unique swelling characteristics of PVA (no swelling in Ethanol, partial swelling in mEthanol and extensive swelling in water) and to the Fuel blocking and swelling suppression properties of silica particles. The membranes are promising for DEFC applications since a high concentration of Fuel may be used to reduce Fuel crossover and to improve the anode kinetics for a resultant increase in both the energy and power densities of the Fuel cell.
Weijiang Zhou - One of the best experts on this subject based on the ideXlab platform.
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direct Ethanol Fuel cells based on ptsn anodes the effect of sn content on the Fuel cell performance
Journal of Power Sources, 2005Co-Authors: Weijiang Zhou, Shuqin Song, S. Douvartzides, Qin Xin, Z.-h. Zhou, Gongquan Sun, Panagiotis TsiakarasAbstract:Abstract In the present work, several carbon supported PtSn catalysts with different Pt/Sn atomic ratios were synthesized and characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Both the results of TEM and XRD showed that all in-house prepared carbon supported Pt and PtSn catalysts had nanosized particles with narrow size distribution. According to the primary analysis of XPS results, it was confirmed that the main part of Pt of the as-prepared catalysts is in metallic state while the main part of Sn is in oxidized state. The performances of single direct Ethanol Fuel cells were different from each other with different anode catalysts and at different temperatures. It was found that, the single DEFC employing Pt3Sn2/C showed better performance at 60 °C while the direct Ethanol Fuel cells with Pt2Sn1/C and Pt3Sn2/C exhibited similar performances at 75 °C. Furthermore, at 90 °C, Pt2Sn1/C was identified as a more suitable anode catalyst for direct Ethanol Fuel cells in terms of the Fuel cell maximum power density. Surface oxygen-containing species, lattice parameters and ohmic effects, which are related to the Sn content, are thought as the main factors influencing the catalyst activity and consequently the performance of single direct Ethanol Fuel cells.
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Direct Ethanol Fuel cells based on PtSn anodes:the effect of Sn content on the Fuel cell performance
Journal of Power Sources, 2005Co-Authors: Weijiang Zhou, Shuqin Song, S. Douvartzides, Qin Xin, Z.-h. Zhou, Wenzhen Li, G-q Sun, Panagiotis TsiakarasAbstract:In the present work, several carbon supported ptsn catalysts with different pt/sn atomic ratios were synthesized and characterized by x-ray diffraction (xrd), transmission electron microscopy (tem) and x-ray photoelectron spectroscopy (xps). both the results of tem and xrd showed that all in-house prepared carbon supported pt and ptsn catalysts had nanosized particles with narrow size distribution. according to the primary analysis of xps results, it was confirmed that the main part of pt of the as-prepared catalysts is in metallic state while the main part of sn is in oxidized state. the performances of single direct Ethanol Fuel cells were different from each other with different anode catalysts and at different temperatures. it was found that, the single defc employing pt3sn2/c showed better performance at 60degreesc while the direct Ethanol Fuel cells with pt2sn1/c and pt3sn2/c exhibited similar performances at 75 degreesc. furthermore, at 90 degreesc, pt2sn1/c was identified as a more suitable anode catalyst for direct Ethanol Fuel cells in terms of the Fuel cell maximum power density. surface oxygen-containing species, lattice parameters and ohmic effects, which are related to the sn content, are thought as the main factors influencing the catalyst activity and consequently the performance of single direct Ethanol Fuel cells. (c) 2004 elsevier b.v. all rights reserved.
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pt based anode catalysts for direct Ethanol Fuel cells
Applied Catalysis B-environmental, 2003Co-Authors: Weijiang ZhouAbstract:Abstract In the present work several Pt-based anode catalysts supported on carbon XC-72R were prepared with a novel method and characterized by means of XRD, TEM and XPS analysis. It was found that all these catalysts are consisted of uniform nanosized particles with sharp distribution and Pt lattice parameter decreases with the addition of Ru or Pd and increases with the addition of Sn or W. Cyclic voltammetry (CV) measurements and single direct Ethanol Fuel cell (DEFC) tests jointly showed that the presence of Sn, Ru and W enhances the activity of Pt towards Ethanol electro-oxidation in the following order: Pt1Sn1/C>Pt1Ru1/C>Pt1W1/C>Pt1Pd1/C>Pt/C. Moreover, Pt1Ru1/C further modified by W and Mo showed improved Ethanol electro-oxidation activity, but its DEFC performance was found to be inferior to that measured for Pt1Sn1/C. Under this respect, several PtSn/C catalysts with different Pt/Sn atomic ratio were also identically prepared and characterized and their direct Ethanol Fuel cell performances were evaluated. It was found that the single direct Ethanol Fuel cell having Pt1Sn1/C or Pt3Sn2/C or Pt2Sn1/C as anode catalyst showed better performances than those with Pt3Sn1/C or Pt4Sn1/C. It was also found that the latter two cells exhibited higher performances than the single cell using Pt1Ru1/C, which is exclusively used in PEMFC as anode catalyst for both mEthanol electro-oxidation and CO-tolerance. This distinct difference in DEFC performance between the catalysts examined here would be attributed to the so-called bifunctional mechanism and to the electronic interaction between Pt and additives. It is thought that an amount of –OHads, an amount of surface Pt active sites and the conductivity effect of PtSn/C catalysts would determine the activity of PtSn/C with different Pt/Sn ratios. At lower temperature values or at low current density regions where the electro-oxidation of Ethanol is considered not so fast and its chemisorption is not the rate-determining step, the Pt3Sn2/C seems to be more suitable for the direct Ethanol Fuel cell. At 75 °C, the single Ethanol Fuel cell with Pt3Sn2/C as anode catalyst showed a comparable performance to that with Pt2Sn1/C, but at higher temperature of 90 °C, the latter presented much better performance. It is thought from a practical point of view that Pt2Sn1/C, supplying sufficient –OHads and having adequate active Pt sites and acceptable ohmic effect, could be the appropriate anode catalyst for DEFC.