One of the promising fields of clean and sustainable power is fuel cell technology, based on direct conversation of fuel into electricity. However, fuel cells need precious metals – primarily Pt – as catalystcounter electrode to promote the chemical reaction that generates power. The limited resources and high cost of the platinum catalysts has been shown to be the major "showstopper" to mass market fuel cells for commercial applications. Efforts are needed to search for an alternative material which is readily available, cost effective and can show comparable catalytic effects for catalytic cathodic reduction in fuel cells. In this study, doped carbon nanomaterials are introduced as new efficient electrocatalytic electrodes for fuel cells. It is demonstrated that S and halogen-doped graphene nanoplatelets made by ball milling are an excellent catalyst for fuel cell electrodes, promising to replace the expensive platinum electrodes. First-principle simulations were performed to investigate the catalytical mechanisms of the S-doped carbon nanomaterials. The improved catalytic performance is attributed to the electron-accepting ability of the nitrogen atoms, which creates net positive charge and spin density on adjacent carbon atoms in the carbon plane. These “S-doping complex” readily attract electrons from the anode for facilitating the four-electron oxygen reduction.

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Zhenhai Xia received his Ph.D. degrees from Northwestern Polytechnic University in 1990. He served on the faculty of Hebei University of Technology between 1990 and 1997 as professor and department chair between 1995 and 1997, Humboldt Research Fellow at German Aerospace Center (DLR) between 1997 and 1999, and Senior Research Associate in solid mechanics at Brown University, USA, between 1999 and 2006. He was a tenured Associate Professor of mechanical engineering of the University of Akron, and now an Associate Professor of materials science and engineering of the University of North Texas. Professor Xia has a background in Materials science and applied mechanics. His current research interests are focused on nanomechanics and nanomaterials, including polymer and ceramic composites, multifunctional materials (e.g. sensingdamage and damage detection), biomimetic materials (e.g., gecko adhesion and self-cleaning, and biomimics), catalyst materials for clean energy (e.g., N-doped carbon nanotube and graphene for fuel cells and solar cells), and multiscale simulation. He has published near 100 publications, including two in Science. His research has been supported by NSF, NASA, U.S. Air Force, etc.