@article{a8f69a6e0fc24401a1d359277d5d94c5,
title = "Single-Site, Single-Metal-Atom, Heterogeneous Electrocatalyst: Metal–Organic-Framework Supported Molybdenum Sulfide for Redox Mediator-Assisted Hydrogen Evolution Reaction",
abstract = "Synthesis of single-site catalysts, whereby the local structure and surrounding chemical environments are identical, has been challenging, particularly in heterogeneous catalysis, as the support often presents spectrum of chemically distinct binding sites. Yet, the above criteria are crucial in attributing the apparent catalytic performance to the structural motif. The presented work augments on our previous work using monometallic molybdenum sulfide tethered within a zirconium-based metal-organic framework (MOF), NU-1000; the monometallic nature enables all presented sites to be catalytically addressable. As the molybdenum sulfide species resided within two distinct pores (micro- and mesopores) of the MOF support, we have imparted uniformity in the local chemical environment by reducing the pore heterogeneity down to a single mesopore. Single-site and single-atom nature of the candidate catalyst was established via X-ray diffraction measurements. Redox mediators were implemented, which, under reductive potentials, provide reduced species; they can effectively deliver the necessary reducing equivalences to the catalytic units that can otherwise not be addressed electrochemically due to the low electron mobility within the framework. Our results indicate the micropore-allocated molybdenum sulfide is approximately four times more active as that in mesopores, whereas its catalytic mechanism is identical, underscoring the importance of controlling chemical environment beyond the active site.",
keywords = "electrocatalysis, hydrogen evolution reaction, metal**organic framework, molybdenum sulfide, redox mediator",
author = "Hyunho Noh and Ying Yang and Xuan Zhang and Goetjen, {Timothy A.} and Syed, {Zoha H.} and Zhiyong Lu and Sol Ahn and Farha, {Omar K.} and Hupp, {Joseph T.}",
note = "Funding Information: This work was supported as part of the Center for Light Energy Activated Redox Processes (LEAP), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award #DE-SC0001059. H.N. gratefully acknowledges support from the Ryan Fellowship program of the Northwestern University International Institute of Nanotechnology. Z.L. acknowledges the support from the National Natural Science Foundation of China (Grant No. 21601047). This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. (DGE-1842165) (Z.H.S.). This work made use of the J. B. Cohen X-ray Diffraction, EPIC, IMSERC, and KECK II facilities of Northwestern University's NUANCE Center, which has received support from the Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF ECCS-1542205); the MRSEC program (NSF DMR1720139) at the Materials Research Center; the Institute for Nanotechnology (IIN); the Keck Foundation; and the State of Illinois, through the IIN. MRCAT operations are supported by the Department of Energy and the MRCAT member institutions. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. Finally, J.T.H. acknowledges Dick Crooks′ scientific influence upon his own work, and Dick's friendship and professional kindness over the years. Congratulations, Dick, on an impressive and accomplished lifetime of professional mentoring and scholarly contributions. Funding Information: This work was supported as part of the Center for Light Energy Activated Redox Processes (LEAP), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award #DE‐SC0001059. H.N. gratefully acknowledges support from the Ryan Fellowship program of the Northwestern University International Institute of Nanotechnology. Z.L. acknowledges the support from the National Natural Science Foundation of China (Grant No. 21601047). This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. (DGE‐1842165) (Z.H.S.). This work made use of the J. B. Cohen X‐ray Diffraction, EPIC, IMSERC, and KECK II facilities of Northwestern University's NUANCE Center, which has received support from the Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF ECCS‐1542205); the MRSEC program (NSF DMR1720139) at the Materials Research Center; the Institute for Nanotechnology (IIN); the Keck Foundation; and the State of Illinois, through the IIN. MRCAT operations are supported by the Department of Energy and the MRCAT member institutions. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE‐AC02‐06CH11357. Finally, J.T.H. acknowledges Dick Crooks′ scientific influence upon his own work, and Dick's friendship and professional kindness over the years. Congratulations, Dick, on an impressive and accomplished lifetime of professional mentoring and scholarly contributions. Publisher Copyright: {\textcopyright} 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim",
year = "2020",
month = jan,
day = "17",
doi = "10.1002/celc.201901650",
language = "English (US)",
volume = "7",
pages = "509--516",
journal = "ChemElectroChem",
issn = "2196-0216",
publisher = "John Wiley and Sons Ltd",
number = "2",
}