Recent Advances on Non‐precious Metal Porous Carbon‐based Electrocatalysts for Oxygen Reduction Reaction

Abstract

Oxygen reduction reaction (ORR) is a crucial process for several significant energy conversion and storage devices, such as metal-air batteries and fuel cells. However, the sluggish kinetics caused by huge activation energy barriers limit the performance. Platinum (Pt) and Pt-based catalysts are still the most efficient catalysts for ORR. Unfortunately, the scarcity, high cost, poor stability, crossover effect and CO poisoning of Pt and Ptbased materials restrict their further development. Carbonbased nanomaterials, especially the non-precious metal porous carbon-based materials (NPC) have been considered as the most promising replacement for Pt and attract the extensive attention of scientists since its high specific surface area and easy regulation can significantly increase the active sites and mass transfer of electrocatalyst. On the other way, the NPC can also be the support of the single metal atoms which can act as the highly efficient ORR electrocatalysts. This review focuses on the recent progress on the applications of NPC at ORR electrocatalyst field.

Charge Transfer Modulated Activity of Carbon‐Based Electrocatalysts

“…Carbon with high specific surface area, high electrical conductivity, abundant defects, and high heteroatoms doping provides the electrocatalysts with the efficient three‐phase interface and abundant active sites. The results have confirmed the synergetic effect of defects and heteroatom doping …”

“…Atomically dispersing metal atoms on supports is advantageous for maximizing metal utilization for fabricating cost‐effective catalysts based on Earth‐scarce metals . Recently, the booming development of advanced characterization techniques has enabled the research of the electrical and structural properties of multitudinous single‐atom catalysts, especially for carbon‐based supports . The excellent activity, high stability, and maximum atomic utilization of SACs made it the promising substitute for precious metal electrocatalysts .…”

Mn3O4@C Nanoparticles Supported on Porous Carbon as Bifunctional Oxygen Electrodes and their Electrocatalytic Mechanism

“…Especially, metal‐air batteries have garnered increasing interest due to the excellent specific energy. But, there are still challenges how to efficiently electro‐catalyze the oxygen evolution reaction (OER) in anode and the oxygen reduction reaction (ORR) in cathode . Although major significant breakthroughs in related technologies, researchers are still looking for materials that can meet commercialized applications.…”

Importance of Electrocatalyst Morphology for the Oxygen Reduction Reaction

“…Porous materials usually have large surface area, which could afford much more active sites and facilitate the mass/charge transfer during the electrocatalytic process ,. Therefore, 3D porous M−N−C materials also have excellent electrocatalytic activity for ORR . Among all methods in constructing pores, the templating method is a powerful strategy ,.…”