Carbon Nanofibers as Potential Catalyst Support for Fuel Cell Cathodes: A Review

Abstract

Polymer electrolyte membrane fuel cells (PEMFCs) are a fast growing next-generation energy conversion technology, which hold promising interest for transportation and other applications. Nevertheless, successful commercialization of PEMFCs has been significantly retarded principally due to the high cost and poor durability of Pt/C catalysts used for anodic and cathodic reactions. Under typical fuel cell operating conditions, a traditional Pt/C catalyst is prone to degrade by various mechanisms, such as electrochemical carbon corrosion, which results in detrimental effects on the long-term performance. There have been tremendous efforts undertaken to develop durable carbon supports by introducing graphitic carbon components. In this context, carbon nanofiber supported catalysts have been investigated as highly durable supports for Pt and non-Pt nanoparticles in recent years. We anticipate it is timely to review the developments in this topic. This Review highlights the current progress on the graphitic nanofibers as a catalyst support in terms of morphology, electrocatalytic activity, various functionalization strategies, and so on, specifically focusing on the effect of nanofiber edge carbons and the advantages of surface reconstruction of nanofiber edge carbon into loops with regard to the stability of carbon support and fuel cell performance. We believe this Review stands as a guide for future researchers to figure out a rational design of oxygen reduction reaction catalysts, especially dealing with highly graphitized carbons.

Insights into the electrocatalytic behavior of nitrogen and sulfur co-doped carbon nanotubes toward oxygen reduction reaction in alkaline media

“…Although N-doped CNTs were sufficiently explored, the simultaneous N and S doping (or co-doping with one precursor) is less explored due to the lack of synthesis methods. Two synthesis strategies are mainly adopted to fabricate heteroatom-doped carbon structures, namely in situ and ex situ methods [15]. In situ methods involve the mixing of heteroatom precursors during the growth of carbon structures (CNTs or graphene).…”

High-corrosion-resistance mechanism of graphitized platelet-type carbon nanofibers in the OER in a concentrated alkaline electrolyte

“…1l), possibly reducing the high surface energy of dangling bonds at the sidewalls of the pCNFs. 56 The X-ray diffraction (XRD) patterns of the carbon materials shown in Fig. 2a reveal a strong peak at approximately 2q ¼ 26 and a relatively weak diffraction peak at approximately 2q ¼ 42 , corresponding to the 002 and 10 reections of graphitic carbon, respectively.…”

Recent Advances in Machine Learning Research for Nanofluid-Based Heat Transfer in Renewable Energy System

“…That is why NFs are preferred for use in thermal management systems and heat transfer devices . At present NFs are being used in solar collectors, hydroelectric rotors, geothermal heat exchangers, , wind turbines, fuel cells, , chemical process plants, and photovoltaic/thermal (PV/T) systems. , …”

“…19 That is why NFs are preferred for use in thermal management systems and heat transfer devices. 20 At present NFs are being used in solar collectors, 21 hydroelectric rotors, 22 geothermal heat exchangers, 23,24 wind turbines, 25 fuel cells, 26,27 chemical process plants, 28 and photovoltaic/thermal (PV/T) systems. 29,30 The addition of nanosized particles to base fluids has a greater impact on the thermophysical characteristics of nanofluids.…”