Abstract
The electrical performance of a proton exchange membrane fuel cell is limited by the slow oxygen reduction reaction (ORR) kinetics. Catalytic improvements for the ORR have been obtained on alloyed PtM/C or M-rich-core@Pt-rich-shell/C catalysts (where M is an early or late transition metal) in comparison to pure Pt/C, due to a combination of strain and ligand effects. However, the effect of the fine nanostructure of the nanomaterials on the ORR kinetics remains underinvestigated. Here, nanometer-sized PtNi/C electrocatalysts with low Ni content (∼15 atom %) but different nanostructures and different densities of grain boundary were synthesized: solid, hollow, or “sea sponge” PtNi/C nanoalloys, and solid Ni-core@Pt-shell/C nanoparticles. These nanostructures were characterized by transmission and scanning transmission electron microscopy, X-ray energy dispersive spectroscopy, synchrotron wide-angle X-ray scattering (WAXS), atomic absorption spectroscopy, and electrochemical techniques. Their electrocatalyti...
Highlights
The United Nations Climate Change Conference (COP 21 or CMP 11) held in Paris in December 2015 has expressed the willingness of 195 states to lower their greenhouse gas emissions and increase their energy efficiency and the ratio of renewable sources in their energy portfolio
The results show that, at fixed Ni content, oxygen reduction reaction (ORR) activity can be tuned by nanostructuring
The PtNi/C nanoparticles are formed by the coreduction of dissolved Pt and Ni salts in the presence of a high-surface-area carbon support dispersed in ethylene glycol (EG)
Summary
The United Nations Climate Change Conference (COP 21 or CMP 11) held in Paris in December 2015 has expressed the willingness of 195 states to lower their greenhouse gas emissions (mostly carbon dioxide and methane) and increase their energy efficiency and the ratio of renewable sources in their energy portfolio. The transportation sector is crucial for the development of a carbon-free landscape.[1] considerable efforts are being devoted worldwide to develop “electromobility”, as shown by the investment of 16 billion US dollars in infrastructures, fiscal incentives, and research and development in favor of electric vehicles realized by United States, United Kingdom, China, Japan, Germany, and France between 2008 and 2014.2 Low-temperature fuel cells, in particular proton exchange membrane fuel cells (PEMFC) using hydrogen, play a key role in this energy transition. The high energetic density of hydrogen (33 kWh kg−1) and the ability of PEMFCs to be refueled (instead of being recharged as is the case for battery-based vehicles) make them interesting for automotive applications.[3,4]. The high cost and limited durability of PEMFC systems still hinder their widespread development.[5,6] The high cost of PEMFC electrodes is mainly due to the large quantity of platinum (Pt) needed to activate the slow oxygen reduction
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
