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  • Identification of the structure of the Bi promoted Pt non-oxidative coupling of methane catalyst: a nanoscale Pt 3 Bi intermetallic alloy
Title: Identification of the structure of the Bi promoted Pt non-oxidative coupling of methane catalyst: a nanoscale Pt 3 Bi intermetallic alloy
Recently, stable non-oxidative conversion of methane (NOCM) for up to 8 h with a C 2 selectivity greater than 90% has been reported over Pt–Bi/ZSM-5 at moderate temperatures (600–700 °C). In this study, we show that the structure of the bimetallic nanoparticles on Pt–Bi/ZSM-5 catalyst is similar to Pt–Bi/SiO 2 . EXAFS indicates the formation of Pt-rich bimetallic Pt–Bi nanoparticles with Pt–Bi bond distance of 2.80 Å. The XRD spectra (on SiO 2 ) are consistent with cubic, intermetallic surface Pt 3 Bi phase on a Pt core. The Pt 3 Bi structure is not known in the thermodynamic phase diagram. In all catalysts, only a small fraction of Bi alloys with Pt. At high Bi loadings, excess Bi reduces at high temperature, covering the catalytic surface leading to a loss in activity. At lower Bi loadings with little excess Bi, the Pt 3 Bi surface is effective for non-oxidative coupling of CH 4 (on ZSM-5) and propane dehydrogenation (on SiO 2 ).  more » « less
Award ID(s):
1647722
PAR ID:
10430718
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Catalysis Science & Technology
Volume:
9
Issue:
6
ISSN:
2044-4753
Page Range / eLocation ID:
1349 to 1356
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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