The Experts below are selected from a list of 13359 Experts worldwide ranked by ideXlab platform
Yongdong Wang - One of the best experts on this subject based on the ideXlab platform.
-
imidazolium functionalized polysulfone hydroxide exchange membranes for potential applications in alkaline membrane direct Alcohol Fuel cells
International Journal of Hydrogen Energy, 2012Co-Authors: Gaohong He, Shuang Gu, Xuemei Wu, Liguang Du, Yongdong WangAbstract:Abstract A series of imidazolium-functionalized polysulfones were successfully synthesized by chloromethylation-Menshutkin two-step method. PSf-ImOHs show the desired selective solubility: insoluble in Alcohols (e.g., methanol and ethanol), and soluble in 50 vol.% aqueous solutions of acetone or tetrahydrofuran, implying their potential applications for both the Alcohol-resistant membranes themselves and the ionomer solutions in low-boiling-point water-soluble solvents. PSf-ImOH also possesses very high thermal stability ( T OD : 258 °C), higher than quaternary ammonium and quaternary phosphonium functionalized polysulfones ( T OD : 120 °C and 186 °C, repsectively). Ion exchange capacity (IEC) of PSf-ImOH membranes ranges from 0.78 to 2.19 mmol g −1 with degree of chloromethylation from 42% to 132% of original chloromethylated polysulfone. As expected, water uptake, swelling ratio, and hydroxide conductivity increase with IEC and temperatures. With 2.19 mmol g −1 of IEC, the PSf-ImOH 132% membrane exhibits the highest hydroxide conductivity (53 mS cm −1 at 20 °C), higher than those of all other reported polysulfone-based HEMs (1.6–45 mS cm −1 ) and other imidazolium-functionalized HEMs (19.6–38.8 mS cm −1 ). In addition, PSf-ImOH membranes have low methanol permeability of 0.8–4.7 × 10 −7 cm 2 s −1 , one order of magnitude smaller than that of Nafion212 membrane. All these properties indicate imidazolium-functionalized polysulfone is very promising for potential applications in alkaline membrane direct Alcohol Fuel cells.
-
imidazolium functionalized polysulfone hydroxide exchange membranes for potential applications in alkaline membrane direct Alcohol Fuel cells
International Journal of Hydrogen Energy, 2012Co-Authors: Xiaoming Yan, Yongdong WangAbstract:Abstract A series of imidazolium-functionalized polysulfones were successfully synthesized by chloromethylation-Menshutkin two-step method. PSf-ImOHs show the desired selective solubility: insoluble in Alcohols (e.g., methanol and ethanol), and soluble in 50 vol.% aqueous solutions of acetone or tetrahydrofuran, implying their potential applications for both the Alcohol-resistant membranes themselves and the ionomer solutions in low-boiling-point water-soluble solvents. PSf-ImOH also possesses very high thermal stability ( T OD : 258 °C), higher than quaternary ammonium and quaternary phosphonium functionalized polysulfones ( T OD : 120 °C and 186 °C, repsectively). Ion exchange capacity (IEC) of PSf-ImOH membranes ranges from 0.78 to 2.19 mmol g −1 with degree of chloromethylation from 42% to 132% of original chloromethylated polysulfone. As expected, water uptake, swelling ratio, and hydroxide conductivity increase with IEC and temperatures. With 2.19 mmol g −1 of IEC, the PSf-ImOH 132% membrane exhibits the highest hydroxide conductivity (53 mS cm −1 at 20 °C), higher than those of all other reported polysulfone-based HEMs (1.6–45 mS cm −1 ) and other imidazolium-functionalized HEMs (19.6–38.8 mS cm −1 ). In addition, PSf-ImOH membranes have low methanol permeability of 0.8–4.7 × 10 −7 cm 2 s −1 , one order of magnitude smaller than that of Nafion212 membrane. All these properties indicate imidazolium-functionalized polysulfone is very promising for potential applications in alkaline membrane direct Alcohol Fuel cells.
Kouakou Boniface Kokoh - One of the best experts on this subject based on the ideXlab platform.
-
Activity of platinum–tin catalysts prepared by the Pechini–Adams method for the electrooxidation of ethanol
Journal of Electroanalytical Chemistry, 2009Co-Authors: F.l.s. Purgato, J.-m. Léger, Claude Lamy, Paulo Olivi, A.r. De Andrade, G. Tremiliosi-filho, Ernesto Rafael Gonzalez, Kouakou Boniface KokohAbstract:Abstract Pt–Sn electrocatalysts of different compositions were prepared and dispersed on carbon Vulcan XC-72 using the Pechini–Adams method. The catalysts were characterized by energy dispersive X-ray analysis and X-ray diffraction. The electrochemical properties of these electrode materials were also examined by cyclic voltammetry and chronoamperometric experiments in acid medium. The results showed that the presence of Sn greatly enhances the activity of Pt towards the electrooxidation of ethanol. Moreover, it contributes to reduce the amount of noble metal in the anode of direct Alcohol Fuel cells, which remains one of the challenges to make the technology of direct Alcohol Fuel cells possible. Electrolysis of ethanol solutions at 0.55 V vs . RHE allowed to determine by liquid chromatography acetaldehyde and acetic acid as the main reaction products. CO 2 was also analyzed after trapping it in a NaOH solution indicating that the cleavage of the C–C bond in the ethanol molecule did occur during the adsorption process. In situ IR reflectance spectroscopy helped to investigate in more details the reaction mechanism through the identification of the reaction products as well as the presence of some intermediate adsorbed species, such as linearly bonded carbon monoxide.
-
Activity of platinum–tin catalysts prepared by the Pechini–Adams method for the electrooxidation of ethanol
Journal of Electroanalytical Chemistry, 2009Co-Authors: F.l.s. Purgato, J.-m. Léger, C. Lamy, Paulo Olivi, A.r. De Andrade, G. Tremiliosi-filho, Ernesto Rafael Gonzalez, Kouakou Boniface KokohAbstract:Pt-Sn electrocatalysts of different compositions were prepared and dispersed on carbon Vulcan XC-72 using the Pechini-Adams method. The catalysts were characterized by energy dispersive X-ray analysis and X-ray diffraction. The electrochemical properties of these electrode materials were also examined by cyclic voltammetry and chronoamperometric experiments in acid medium. The results showed that the presence of Sn greatly enhances the activity of Pt towards the electrooxidation of ethanol. Moreover, it contributes to reduce the amount of noble metal in the anode of direct Alcohol Fuel cells, which remains one of the challenges to make the technology of direct Alcohol Fuel cells possible. Electrolysis of ethanol solutions at 0.55 V vs. RHE allowed to determine by liquid chromatography acetaldehyde and acetic acid as the main reaction products. CO(2) was also analyzed after trapping it in a NaOH solution indicating that the cleavage of the C-C bond in the ethanol molecule did occur during the adsorption process. In situ IR reflectance spectroscopy helped to investigate in more details the reaction mechanism through the identification of the reaction products as well as the presence of some intermediate adsorbed species, such as linearly bonded carbon monoxide. (C) 2009 Elsevier B.V. All rights reserved.CAPES/COFECUB[498/05]CAPES[0509078]FAPESP, Brazi
J.-m. Léger - One of the best experts on this subject based on the ideXlab platform.
-
Activity of platinum–tin catalysts prepared by the Pechini–Adams method for the electrooxidation of ethanol
Journal of Electroanalytical Chemistry, 2009Co-Authors: F.l.s. Purgato, J.-m. Léger, Claude Lamy, Paulo Olivi, A.r. De Andrade, G. Tremiliosi-filho, Ernesto Rafael Gonzalez, Kouakou Boniface KokohAbstract:Abstract Pt–Sn electrocatalysts of different compositions were prepared and dispersed on carbon Vulcan XC-72 using the Pechini–Adams method. The catalysts were characterized by energy dispersive X-ray analysis and X-ray diffraction. The electrochemical properties of these electrode materials were also examined by cyclic voltammetry and chronoamperometric experiments in acid medium. The results showed that the presence of Sn greatly enhances the activity of Pt towards the electrooxidation of ethanol. Moreover, it contributes to reduce the amount of noble metal in the anode of direct Alcohol Fuel cells, which remains one of the challenges to make the technology of direct Alcohol Fuel cells possible. Electrolysis of ethanol solutions at 0.55 V vs . RHE allowed to determine by liquid chromatography acetaldehyde and acetic acid as the main reaction products. CO 2 was also analyzed after trapping it in a NaOH solution indicating that the cleavage of the C–C bond in the ethanol molecule did occur during the adsorption process. In situ IR reflectance spectroscopy helped to investigate in more details the reaction mechanism through the identification of the reaction products as well as the presence of some intermediate adsorbed species, such as linearly bonded carbon monoxide.
-
Activity of platinum–tin catalysts prepared by the Pechini–Adams method for the electrooxidation of ethanol
Journal of Electroanalytical Chemistry, 2009Co-Authors: F.l.s. Purgato, J.-m. Léger, C. Lamy, Paulo Olivi, A.r. De Andrade, G. Tremiliosi-filho, Ernesto Rafael Gonzalez, Kouakou Boniface KokohAbstract:Pt-Sn electrocatalysts of different compositions were prepared and dispersed on carbon Vulcan XC-72 using the Pechini-Adams method. The catalysts were characterized by energy dispersive X-ray analysis and X-ray diffraction. The electrochemical properties of these electrode materials were also examined by cyclic voltammetry and chronoamperometric experiments in acid medium. The results showed that the presence of Sn greatly enhances the activity of Pt towards the electrooxidation of ethanol. Moreover, it contributes to reduce the amount of noble metal in the anode of direct Alcohol Fuel cells, which remains one of the challenges to make the technology of direct Alcohol Fuel cells possible. Electrolysis of ethanol solutions at 0.55 V vs. RHE allowed to determine by liquid chromatography acetaldehyde and acetic acid as the main reaction products. CO(2) was also analyzed after trapping it in a NaOH solution indicating that the cleavage of the C-C bond in the ethanol molecule did occur during the adsorption process. In situ IR reflectance spectroscopy helped to investigate in more details the reaction mechanism through the identification of the reaction products as well as the presence of some intermediate adsorbed species, such as linearly bonded carbon monoxide. (C) 2009 Elsevier B.V. All rights reserved.CAPES/COFECUB[498/05]CAPES[0509078]FAPESP, Brazi
-
electrocatalytic oxidation of aliphatic Alcohols application to the direct Alcohol Fuel cell dafc
Journal of Applied Electrochemistry, 2001Co-Authors: C Lamy, El Mustapha Belgsir, J.-m. LégerAbstract:The electrooxidation of some low molecular weight Alcohols, such as ethanol, ethylene glycol and n-propanol, is discussed in terms of reaction mechanisms and catalytic activity of the anode material. Some examples of a single cell, using a proton exchange membrane (PEM) as electrolyte, are given to illustrate interesting results, particularly for the direct electrooxidation of ethanol. This Alcohol may replace methanol in a direct Alcohol Fuel cell.
Kenneth I Ozoemena - One of the best experts on this subject based on the ideXlab platform.
-
nanostructured platinum free electrocatalysts in alkaline direct Alcohol Fuel cells catalyst design principles and applications
RSC Advances, 2016Co-Authors: Kenneth I OzoemenaAbstract:The alkaline direct Alcohol Fuel cell (ADAFC) is an environmentally friendly electrochemical energy source that can drive a plethora of consumer and portable electronics. Research in ADAFCs has continued to attract major attention due to their several advantages over conventional proton-exchange membrane Fuel cells (PEMFC); these include the emergence of anion-exchange membranes (AEM), easy handling of liquid Alcohol Fuels compared to hydrogen, higher volumetric energy densities of Alcohols compared to hydrogen, enhanced reaction kinetics of Alcohols and oxygen reduction reaction in alkaline media. Further developments in this field are dependent on improving the performance of nanostructured electrocatalysts and AEMs. This review is an overview of some notable advances made in recent years. Importantly, it provides an excellent insight into the fundamental principles that allow for the intelligent design and synthesis of non-precious metal nanostructured electrocatalysts for the cathode and anode reactions of ADAFCs. This review is an attempt to find answers to questions such as “Why should I use a particular catalyst for the ADAFC?”, “What are the underlying principles that must inform my choice in designing such a catalyst?”, and “What synthesis method(s) or catalyst supports should be considered to prepare catalysts with the appropriate physicochemical properties for high-performance?” The knowledge provided in this review can be applied not only to ADAFCs, but also to several other electrocatalytic systems (such as various other Fuel cell systems, electrochemical sensors, and metal–air batteries).
F.l.s. Purgato - One of the best experts on this subject based on the ideXlab platform.
-
Activity of platinum–tin catalysts prepared by the Pechini–Adams method for the electrooxidation of ethanol
Journal of Electroanalytical Chemistry, 2009Co-Authors: F.l.s. Purgato, J.-m. Léger, Claude Lamy, Paulo Olivi, A.r. De Andrade, G. Tremiliosi-filho, Ernesto Rafael Gonzalez, Kouakou Boniface KokohAbstract:Abstract Pt–Sn electrocatalysts of different compositions were prepared and dispersed on carbon Vulcan XC-72 using the Pechini–Adams method. The catalysts were characterized by energy dispersive X-ray analysis and X-ray diffraction. The electrochemical properties of these electrode materials were also examined by cyclic voltammetry and chronoamperometric experiments in acid medium. The results showed that the presence of Sn greatly enhances the activity of Pt towards the electrooxidation of ethanol. Moreover, it contributes to reduce the amount of noble metal in the anode of direct Alcohol Fuel cells, which remains one of the challenges to make the technology of direct Alcohol Fuel cells possible. Electrolysis of ethanol solutions at 0.55 V vs . RHE allowed to determine by liquid chromatography acetaldehyde and acetic acid as the main reaction products. CO 2 was also analyzed after trapping it in a NaOH solution indicating that the cleavage of the C–C bond in the ethanol molecule did occur during the adsorption process. In situ IR reflectance spectroscopy helped to investigate in more details the reaction mechanism through the identification of the reaction products as well as the presence of some intermediate adsorbed species, such as linearly bonded carbon monoxide.
-
Activity of platinum–tin catalysts prepared by the Pechini–Adams method for the electrooxidation of ethanol
Journal of Electroanalytical Chemistry, 2009Co-Authors: F.l.s. Purgato, J.-m. Léger, C. Lamy, Paulo Olivi, A.r. De Andrade, G. Tremiliosi-filho, Ernesto Rafael Gonzalez, Kouakou Boniface KokohAbstract:Pt-Sn electrocatalysts of different compositions were prepared and dispersed on carbon Vulcan XC-72 using the Pechini-Adams method. The catalysts were characterized by energy dispersive X-ray analysis and X-ray diffraction. The electrochemical properties of these electrode materials were also examined by cyclic voltammetry and chronoamperometric experiments in acid medium. The results showed that the presence of Sn greatly enhances the activity of Pt towards the electrooxidation of ethanol. Moreover, it contributes to reduce the amount of noble metal in the anode of direct Alcohol Fuel cells, which remains one of the challenges to make the technology of direct Alcohol Fuel cells possible. Electrolysis of ethanol solutions at 0.55 V vs. RHE allowed to determine by liquid chromatography acetaldehyde and acetic acid as the main reaction products. CO(2) was also analyzed after trapping it in a NaOH solution indicating that the cleavage of the C-C bond in the ethanol molecule did occur during the adsorption process. In situ IR reflectance spectroscopy helped to investigate in more details the reaction mechanism through the identification of the reaction products as well as the presence of some intermediate adsorbed species, such as linearly bonded carbon monoxide. (C) 2009 Elsevier B.V. All rights reserved.CAPES/COFECUB[498/05]CAPES[0509078]FAPESP, Brazi