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DOE OSTI · 1617823

Activating low-temperature diesel oxidation by single-atom Pt on TiO 2 nanowire array

Abstract

Supported metal single atom catalysts (SACs) present an emerging class of low-temperature catalysts with high reactivity and selectivity, which, however, face challenges on both durability and practicality. Herein, we report a single-atom Pt catalyst that is strongly anchored on a robust nanowire forest of mesoporous rutile titania grown on the channeled walls of full-size cordierite honeycombs. This Pt SAC exhibits remarkable activity for oxidation of CO and hydrocarbons with 90% conversion at temperatures as low as ~160 °C under simulated diesel exhaust conditions while using 5 times less Pt-group metals than a commercial oxidation catalyst. Such an excellent low-temperature performance is sustained over hydrothermal aging and sulfation as a result of highly dispersed and isolated active single Pt ions bonded at the Ti vacancy sites with 5 or 6 oxygen ions on titania nanowire surfaces.

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BibTeXRIS

Hoang, Son, Guo, Yanbing, Binder, Andrew J., Tang, Wenxiang, Wang, Sibo, Liu, Jingyue (Jimmy), Tran, Huan, Lu, Xingxu, Wang, Yu, Ding, Yong, Kyriakidou, Eleni A., Yang, Ji, Toops, Todd J., Pauly, Thomas R., Ramprasad, Rampi, Gao, Pu-Xian. 2020-02-26. Activating low-temperature diesel oxidation by single-atom Pt on TiO 2 nanowire array. https://doi.org/10.1038/s41467-020-14816-w

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36 MATERIALS SCIENCE↗