Assessing the Pt[sub upd] Surface Area Stability of Pt[sub 1−x]M[sub x] (M=Re, Nb, Bi) Solid Solutions for Proton Exchange Membrane Fuel Cells

2010 ◽  
Vol 157 (5) ◽  
pp. B737 ◽  
Author(s):  
D. A. Stevens ◽  
S. Wang ◽  
R. J. Sanderson ◽  
A. Garsuch ◽  
M. K. Debe ◽  
...  
2019 ◽  
Author(s):  
Kevin Gu ◽  
Eric J. Kim ◽  
Sunil K. Sharma ◽  

<p>Carbon aerogel possesses unique structural and electrical properties, such as high mesopore volume, specific surface area, and electrical conductivity, which make it suitable for use as a catalyst support in Proton Exchange Membrane Fuel Cells (PEMFC). In this study, we present a novel synthesis of highly mesoporous carbon aerogel via ambient-drying and investigate its application in PEMFCs. The structural effects of activation on carbon aerogel were also studied. The TEM, XRF, Non Localized Density Function Theory (NLDFT) and BJH analysis were carried out to observe the morphology and pore structure. Pt on carbon aerogel and activated carbon aerogel show efficient activity in both oxygen reduction and hydrogen oxidation reactions compared to Pt on Vulcan XC-72, with increases up to 715% and 195% in specific power density, respectively. The enhanced performance of carbon aerogel is attributed to its large specific surface area and high mesopore to micropore ratio. Accelerated stress tests show that carbon aerogel has comparable durability with Vulcan XC-72, while activated carbon aerogel is less durable than both materials. Thus, the mesoporous carbon aerogel provides an efficient, lower-cost alternative to existing microporous carbon material as a catalyst support in PEMFCs.</p><p></p>


2017 ◽  
Vol 343 ◽  
pp. 571-579 ◽  
Author(s):  
S. Rasouli ◽  
R.A. Ortiz Godoy ◽  
Z. Yang ◽  
M. Gummalla ◽  
S.C. Ball ◽  
...  

2019 ◽  
Author(s):  
Kevin Gu ◽  
Eric J. Kim ◽  
Sunil K. Sharma ◽  

<p>Carbon aerogel possesses unique structural and electrical properties, such as high mesopore volume, specific surface area, and electrical conductivity, which make it suitable for use as a catalyst support in Proton Exchange Membrane Fuel Cells (PEMFC). In this study, we present a novel synthesis of highly mesoporous carbon aerogel via ambient-drying and investigate its application in PEMFCs. The structural effects of activation on carbon aerogel were also studied. The TEM, XRF, Non Localized Density Function Theory (NLDFT) and BJH analysis were carried out to observe the morphology and pore structure. Pt on carbon aerogel and activated carbon aerogel show efficient activity in both oxygen reduction and hydrogen oxidation reactions compared to Pt on Vulcan XC-72, with increases up to 715% and 195% in specific power density, respectively. The enhanced performance of carbon aerogel is attributed to its large specific surface area and high mesopore to micropore ratio. Accelerated stress tests show that carbon aerogel has comparable durability with Vulcan XC-72, while activated carbon aerogel is less durable than both materials. Thus, the mesoporous carbon aerogel provides an efficient, lower-cost alternative to existing microporous carbon material as a catalyst support in PEMFCs.</p><p></p>


2019 ◽  
Vol 19 (2) ◽  
pp. 877-881 ◽  
Author(s):  
Tai Thien Huynh ◽  
Hau Quoc Pham ◽  
At Van Nguyen ◽  
Son Truong Nguyen ◽  
Long Giang Bach ◽  
...  

2019 ◽  
Author(s):  
Valentina Guccini ◽  
Annika Carlson ◽  
Shun Yu ◽  
Göran Lindbergh ◽  
Rakel Wreland Lindström ◽  
...  

The performance of thin carboxylated cellulose nanofiber-based (CNF) membranes as proton exchange membranes in fuel cells has been measured in-situ as a function of CNF surface charge density (600 and 1550 µmol g<sup>-1</sup>), counterion (H<sup>+</sup>or Na<sup>+</sup>), membrane thickness and fuel cell relative humidity (RH 55 to 95 %). The structural evolution of the membranes as a function of RH as measured by Small Angle X-ray scattering shows that water channels are formed only above 75 % RH. The amount of absorbed water was shown to depend on the membrane surface charge and counter ions (Na<sup>+</sup>or H<sup>+</sup>). The high affinity of CNF for water and the high aspect ratio of the nanofibers, together with a well-defined and homogenous membrane structure, ensures a proton conductivity exceeding 1 mS cm<sup>-1</sup>at 30 °C between 65 and 95 % RH. This is two orders of magnitude larger than previously reported values for cellulose materials and only one order of magnitude lower than Nafion 212. Moreover, the CNF membranes are characterized by a lower hydrogen crossover than Nafion, despite being ≈ 30 % thinner. Thanks to their environmental compatibility and promising fuel cell performance the CNF membranes should be considered for new generation proton exchange membrane fuel cells.<br>


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