PtRu Catalysts on Nitrogen-Doped Carbon Nanotubes with Conformal Hydrogenated TiO2 Shells for Methanol Oxidation

Sekar, Archana; Metzger, Nathaniel; Rajendran, Sabari; Elangovan, Ayyappan; Cao, Yonghai; Peng, Feng; Li, Xianglin; Li, Jun

doi:10.1021/acsanm.1c03742

Title: PtRu Catalysts on Nitrogen-Doped Carbon Nanotubes with Conformal Hydrogenated TiO₂ Shells for Methanol Oxidation

Journal Article · Thu Jan 06 00:00:00 EST 2022 · ACS Applied Nano Materials

DOI:https://doi.org/10.1021/acsanm.1c03742· OSTI ID:1865176

^[1]; Metzger, Nathaniel ^[2]; Rajendran, Sabari ^[1];

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^[3];

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^[2];

^[1]

Kansas State Univ., Manhattan, KS (United States)
Univ. of Kansas School of Engineering, Lawrence, KS (United States)
South China Univ. of Technology, Guangzhou (China)
Guangzhou Univ. (China)

The methanol oxidation reaction (MOR) is the limiting factor in direct methanol fuel cells (DMFC). There is an urgent need to improve the catalytic activity and stability of MOR catalysts. This study reports a highly active PtRu catalyst for MOR based on a hybrid multifunctional catalyst support consisting of a conformal amorphous hydrogenated TiO₂ shell wrapped around the oxygenated N-doped carbon nanotube core, denoted as PtRu/TiO₂/ ONCNT-400. Both the TiO₂ shell and the subsequent PtRu nanoparticles are deposited by a rapid microwave-assisted synthesis processes. The hydrogenated TiO₂ shell is found to exhibit a strong interaction with the deposited PtRu catalyst nanoparticles and effectively prevent them from agglomeration during the postdeposition thermal annealing to form more active crystalline PtRu alloy catalysts. In addition, the defective hydrogenated TiO₂ shell enhances the PtRu catalyst activity by the synergistic effects of partial charge transfer from TiO₂ to PtRu and high oxophilicity, which improves the kinetics of oxidation of poisonous CO intermediate to CO₂. The mass activity for MOR and long-cycling stability of the PtRu/TiO₂/ONCNT-400 catalyst surpass the two benchmark commercial PtRu/C catalysts from Johnson Matthey (JM) and Tanaka KiKinzoku (TKK), respectively. Furthermore, the results demonstrate that PtRu/TiO₂/ONCNT-400 can serve as an efficient catalyst for MOR in DMFC.

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Research Organization:: Kansas State Univ., Manhattan, KS (United States)

Sponsoring Organization:: USDOE Office of Energy Efficiency and Renewable Energy (EERE)

Grant/Contract Number:: EE0008440

OSTI ID:: 1865176

Journal Information:: ACS Applied Nano Materials, Vol. 5, Issue 3; Related Information: The Supporting Information is available free of charge at: https://pubs.acs.org/doi/10.1021/acsanm.1c03742.; ISSN 2574-0970

Publisher:: American Chemical Society (ACS)Copyright Statement

Country of Publication:: United States

Language:: English

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Title: PtRu Catalysts on Nitrogen-Doped Carbon Nanotubes with Conformal Hydrogenated TiO2 Shells for Methanol Oxidation

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Title: PtRu Catalysts on Nitrogen-Doped Carbon Nanotubes with Conformal Hydrogenated TiO₂ Shells for Methanol Oxidation