Recent progress of carbon dots and carbon nanotubes applied in oxygen reduction reaction of fuel cell for transportation

Proton exchange membrane fuel cell (PEMFC) is receiving strong attention in sustainable energy conversion and storage systems. Its high efficiency, low emission, and environmental friendliness enable hydrogen fuel cell electric vehicle (FCEV) for day to day transportation. High costs, limited durability and inefficient oxygen reduction reaction (ORR) have been identified as key challenges for the widespread commercial success of fuel cell transportation vehicles. ORR is constrained by slow kinetics of cathode catalyst and must be improved by suitable nanoengineering of low-cost electrocatalysts. Replacing platinum group metals with carbon-based non-precious metal is a promising solution. Recently, advances in zero-dimensional carbon dots are showing promise for challenging energy-oriented issues. In addition, the one-dimensional carbon nanotubes are also found suitable for efficient ORR. However, carbon-based electrocatalyst showing improved performance in electrochemical measurements are not up to the expectation in the practical application of FCEV. This review highlights the advancement and future opportunities for improving performance of ORR using carbon dots and carbon nanotubes nanostructures. We discussed the application of carbon dots and carbon nanotubes in the fuel cell. Their corresponding electrochemical performance was presented. Followed by, practical application of carbon nanotubes in the real operating condition of PEMFC was discussed. Finally, the current status and future target of FCEV were comprehensively addressed.