scholarly journals Atomically Dispersed M-N-C Catalysts in Proton Exchange Membrane Fuel Cells: Recent Progress and Perspectives

2021 ◽  
Vol 308 ◽  
pp. 01019
Author(s):  
Haoran Kong ◽  
Jiarong Liu ◽  
Yu Yue
Keyword(s):  
Fuel Cells ◽  
Cost Effectiveness ◽  
Proton Exchange Membrane ◽  
High Surface ◽  
High Surface Area ◽  
Chemical Properties ◽  
Proton Exchange ◽  
Synthesis Methods ◽  
Zeolitic Imidazolate Framework ◽  
Exchange Membrane

The selection of oxygen reduction reaction (ORR) catalysts plays a key role in enhancing the performance of proton exchange membrane fuel cells (PEMFCs). To optimize the energy conversion technology in PEMFCs and improve the cost-effectiveness of ORR catalysts, atomically dispersed metal-nitrogen-carbon (M-N-C) catalyst is regarded as one of the most promising materials to replace Pt-based catalysts. In this review, we summarize the advantages of atomically dispersed M-N-C catalysts in both physical and chemical properties, including controllable dimensions, ease of accessibility, high surface area and excellent conductivity. Additionally, the unique merits of their cost-effectiveness are also described by a concise comparison with other ORR catalysts. Subsequently, some of its main synthesis methods are based on the most commonly used zeolitic imidazolate framework (ZIF) precursor. Several other precursors involve carbon, nitrogen, and one or more active transition metals (mainly iron or cobalt) are introduced briefly. Although there are a variety of synthesis methods, all these methods are in line with pyrolysis technology. Then, the recent advancements of atomically dispersed M-N-C catalysts related to their development and application of Fe-N-C, Mn-N-C, and Co-N-C catalysts are comprehensively described. Finally, based on some common M-N-C catalysts, many improvement ideas are also proposed. The focus is on how to control the negative reaction in Fe-N-C catalysts, improve the activity of Co-N-C catalysts and Mn-N-C catalysts, and find more suitable transition metal materials to prepare M-N-C catalysts.

Nanostructured Pt/WOx-C Solids as Electrocatalyst for PEMFC

2012 ◽  
Vol 15 (3) ◽  
pp. 165-170 ◽  
Author(s):  
M.L. Hernández-Pichardo ◽  
R.G. González-Huerta ◽  
P. Del Angel ◽  
E. Palacios-González ◽  
S.P. Paredes-Carrera
Keyword(s):  
Proton Exchange Membrane ◽  
High Surface ◽  
High Surface Area ◽  
Proton Exchange ◽  
Synthesis Methods ◽  
Co Tolerance ◽  
Transmission Electron ◽  
Anode Electrocatalysts ◽  
Exchange Membrane ◽  
Nanostructured Pt

Platinum nanoparticles supported on high surface area carbon black (e.g., Vulcan XC-72) are the most commonly used catalysts for both cathode and anode in proton exchange membrane fuel cells (PEMFCs), however, some other catalysts such as Pt/MoOx and Pt/WOx are also considered promising, due to their higher activity, stability and enhanced CO tolerance. This work is focused on the synthesis and characterization of nanostructured Pt/WOx-C as both cathode and anode electrocatalysts for PEMFCs. The Pt deposit on the surface of the support is a crucial step in the synthesis of the catalytic materials. Because of this, different synthesis methods were probed in order to find the conditions for the higher dispersion and accessibility of Platinum over the WOx-C support and to improve the PEMFC cathode stability. The catalysts were prepared by UV and ultrasound assisted approaches, and characterized by Transmission Electron Microscopy as well as lineal and cyclic voltammetry.

Graphene Based Nafion® Nanocomposite Membranes for Proton Exchange Membrane Fuel Cells

2011 ◽  
Author(s):  
Vinay K. Adigoppula ◽  
Waseem Khan ◽  
Rajib Anwar ◽  
Avni A. Argun ◽  
R. Asmatulu
Keyword(s):  
Proton Exchange Membrane ◽  
High Surface ◽  
High Surface Area ◽  
Volume Ratio ◽  
Thermal Characterization ◽  
Proton Exchange Membranes ◽  
Proton Exchange ◽  
Nanocomposite Membranes ◽  
Exchange Membrane

Nanocomposite proton-exchange membranes are fabricated by loading graphene nanoflakes into perfluoro sulfonic acid polymer (Nafion) solutions at controlled amounts (1–4 wt%) followed by electrical and thermal characterization of the resulting membranes. Electronic and ionic conductivity values of the nanocomposites, as well as their dielectric and thermal properties improve at increased graphene loadings. Owing to graphene’s exceptionally high surface area to volume ratio and excellent physical properties, these nanocomposite are promising candidates for proton-exchange membrane fuel cell applications.

Highly proton conductive membranes based on carboxylated cellulose nanofibres and their performance in proton exchange membrane fuel cells

2019 ◽  
Author(s):  
Valentina Guccini ◽  
Annika Carlson ◽  
Shun Yu ◽  
Göran Lindbergh ◽  
Rakel Wreland Lindström ◽  
...  
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Surface Charge ◽  
Proton Exchange Membrane ◽  
Membrane Surface ◽  
Proton Exchange ◽  
Membrane Thickness ◽  
Fuel Cell Performance ◽  
Cellulose Nanofibres ◽  
Exchange Membrane

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>

Sign in / Sign up

Export Citation Format

Share Document