Integration Construction of Hybrid Electrocatalysts for Oxygen Reduction

Abstract

There is notable progress in the development of efficient oxygen reduction electrocatalysts, which are crucial components of fuel cells. However, these superior activities are limited by imbalanced mass transport and cannot be fully reflected in actual fuel cell applications. Herein, the design concepts and development tracks of platinum (Pt)‐nanocarbon hybrid catalysts, aiming to enhance the performance of both cathodic electrocatalysts and fuel cells, are presented. This review commences with an introduction to Pt/C catalysts, highlighting the diverse architectures developed to date, with particular emphasis on heteroatom modification and microstructure construction of functionalized nanocarbons based on integrated design concepts. This discussion encompasses the structural evolution, property enhancement, and catalytic mechanisms of Pt/C‐based catalysts, including rational preparation recipes, superior activity, strong stability, robust metal‐support interactions, adsorption regulation, synergistic pathways, confinement strategies, ionomer optimization, mass transport permission, multidimensional construction, and reactor upgrading. Furthermore, this review explores the low‐barrier or barrier‐free mass exchange interfaces and channels achieved through the impressive multidimensional construction of Pt‐nanocarbon integrated catalysts, with the goal of optimizing fuel cell efficiency. In conclusion, this review outlines the challenges associated with Pt‐nanocarbon integrated catalysts and provides perspectives on the future development trends of fuel cells and beyond.

Hydrogen Peroxide Spillover on Platinum–Iron Hybrid Electrocatalyst for Stable Oxygen Reduction

“…Developing highly efficient and stable electrocatalysts for cathodic oxygen reduction reaction (ORR) is crucial for proton exchange membrane fuel cells (PEMFCs) . Although platinum (Pt) and its alloy are established options, − low-cost non-noble metal alternatives such as iron–nitrogen–carbon (Fe–N–C) catalysts have emerged as promising candidates due to their potential ORR activity. − However, their tolerance to harsh ORR environments remains a significant challenge. − This challenge stems from two major factors: the structural instability of the Fe–N–C catalyst and the presence of hydrogen peroxide (H 2 O 2 ) as a byproduct of an incomplete reaction. Incomplete ORR leads to H 2 O 2 production, which undergoes a Fenton reaction with leached Fe ions, generating highly reactive hydroxyl radicals ( · OH) and superoxide ( · OOH) radicals .…”