Oxygen reduction electrocatalysis: From conventional to single-atomic platinum-based catalysts for proton exchange membrane fuel cells
image: Nanostructured Pt-based alloys can greatly enhance the electrocatalytic performance, which generally have various morphologies such as wires, networks, and dendrites.
Credit: HIGHER EDUCATION PRESS
The escalating demand for clean and efficient energy has intensified the focus on proton exchange membrane fuel cells (PEMFCs) as a reliable alternative to traditional energy sources. However, the cathodic oxygen reduction reaction (ORR) in PEMFCs, which is sluggish in kinetics, requires highly active electrocatalysts to accelerate the reaction rate. Platinum (Pt)-based materials have been the most efficient choice, yet they face limitations due to scarcity, high cost, and stability issues. The quest for optimizing Pt utilization while enhancing catalytic performance has led to the exploration of single-atomic catalysts.
The review, authored by Cheng YUAN, Shiming ZHANG, and Jiujun ZHANG, offers an in-depth analysis of Pt-based catalysts, focusing on the emerging class of single-atomic catalysts. The researchers explore the impact of Pt particle size on the activation of CO2 and the formation of CO during the dry reforming of methane (DRM) process. The review synthesizes recent findings on the design and synthesis of various isolated, alloyed, and nanoparticle-contained Pt SACs, highlighting the role of metal-support interactions in enhancing ORR activity and stability.
The study reveals that the size of Pt particles significantly influences the catalyst's performance. Notably, the Ni25/MgO catalyst demonstrated optimal resistance to carbon formation and high power density, making it a promising candidate for use in PEMFCs. The review also underscores the importance of understanding the underlying mechanisms of ORR to further improve the performance of Pt SACs.
This review holds profound implications for the advancement of PEMFC technology. The insights provided into the role of Pt particle size in ORR efficiency offer a clear direction for the development of advanced catalysts. The superior performance of the Ni25/MgO catalyst in terms of power density and durability suggests a promising path forward for the optimization of PEMFCs. This work not only advances the scientific understanding of electrocatalysts but also contributes to the broader goals of clean energy production and environmental sustainability.