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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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.
The authors declare no competing interests.
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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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