NEU M-N-C Catalysts
NEU M-N-C Fuel Cell Catalysts with MMC Sites
Recipient Northeastern University (PI: Qingying Jia)
Subs Prof. Sanjeev Mukerjee (Northeastern University), Dr. Adam Weber (Lawrence Berkeley National Laboratory)
Abstract Commercialization of hydrogen fuel cell vehicles was initiated in 2014 in Japan, and later spread to few counties in Europe and few states in United States. The catalysts used for the oxygen reduction reaction (ORR) in the proton exchange membrane fuel cell (PEMFC) are Pt-alloys. Replacing the Pt-alloys with earth-abundant and inexpensive materials holds the key for global commercialization of hydrogen fuel cell vehicles, and many other applications burdened by high Pt loading. By far the leading platinum group metal (PGM) free catalysts for the ORR in PEMFCs are the single transition metal atom (M=Mn, Fe, or Co) embedded in nitrogen-doped carbon matrix (M-N-C). However, the state-of-the-art performance of M-N-C is still insufficient for practical applications, and not durable upon PEMFC operation. Further progress in both activity and durability is needed for practical applications of M-N-C as cathode catalysts in the automobile PEMFCs. In this project we aim to achieve these goals by moving beyond the current leading PGM-free M-N-C catalysts featured with single transition metal atom hosted in nitrogen-doped carbon matrix toward Mx-N-C catalysts with multiple metal center (MMC) sites. Vapor deposition methods including dual ion beam-assisted deposition (IBAD) and sputtering will be applied for low temperature synthesis of M(x)-N-C catalysts with active site densification. IBAD and electrospinning will be used for electrode fabrication. In addition, atomic-scale in situ characterization of active site and mass transport modeling will be studied to understand the origin of the ORR activity of M(x)-N-C catalysts and the degradation mode(s). Northeastern University (NEU) leads the catalyst development, electrode fabrication along with MEA preparation using a variety of techniques, in situ spectroscopic characterization, and initial electrochemical testing. Lawrence Berkeley National Laboratory (LBNL) is leading the mass transport modeling. Catalyst modeling, electrode fabrication, low temperature fuel cell test, and advanced characterizations are conducted in collaboration with consortium national laboratory members.