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Carbon-based metal-free catalysts

An Erratum to this article was published on 04 October 2016

Abstract

Metals and metal oxides are widely used as catalysts for materials production, clean energy generation and storage, and many other important industrial processes. However, metal-based catalysts suffer from high cost, low selectivity, poor durability, susceptibility to gas poisoning and have a detrimental environmental impact. In 2009, a new class of catalyst based on earth-abundant carbon materials was discovered as an efficient, low-cost, metal-free alternative to platinum for oxygen reduction in fuel cells. Since then, tremendous progress has been made, and carbon-based metal-free catalysts have been demonstrated to be effective for an increasing number of catalytic processes. This Review provides a critical overview of this rapidly developing field, including the molecular design of efficient carbon-based metal-free catalysts, with special emphasis on heteroatom-doped carbon nanotubes and graphene. We also discuss recent advances in the development of carbon-based metal-free catalysts for clean energy conversion and storage, environmental protection and important industrial production, and outline the key challenges and future opportunities in this exciting field.

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Figure 1: Timeline showing the important developments of carbon-based metal-free catalysts.
Figure 2: Different types of nitrogen-doped carbon and the reaction mechanisms of the ORR and CO2 reduction.
Figure 3: Design principles for various carbon-based metal-free catalysts.
Figure 4: Applications of metal-free carbon catalysts.

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Acknowledgements

The authors thank colleagues, collaborators and peers whose work was cited in this article, and are also grateful for the financial support from NSF, NSF-NSFC, AFOSR-DoD-MURI, DAGSI, CWRU, The 111 Project (B14004), The State Key Laboratory of Organic-Inorganic Composites, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, and BUCT.

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Correspondence to Liming Dai.

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Liu, X., Dai, L. Carbon-based metal-free catalysts. Nat Rev Mater 1, 16064 (2016). https://doi.org/10.1038/natrevmats.2016.64

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