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Title: Computational screen of M 2 P metal phosphides for catalytic ethane dehydrogenation
Metal phosphides are promising catalysts for hydrocarbon transformations, but computational screening is complicated by their diverse structures and compositions. To disentangle structural from compositional contributions, here we explore the metal-rich M 2 P (M = Fe, Co, Ni, Cu, Mo, Ru, Rh, Pd, Ag, Pt) series in hexagonal and orthorhombic structures that are common to a subset of these materials, using supercell density functional theory (DFT). To understand the contribution of metal choice to utility for catalytic ethane dehydrogenation (EDH), we compute and compare the adsorption of key EDH intermediates across low-index surface terminations. These materials expose both metal and phosphide sites. Calculations show that binding energies at metal sites correlate with the bulk metals, with P incorporation either enhancing or suppressing binding. Phosphide sites compete with metal sites for adsorbates and tend to suppress overactivation by destabilizing highly dehydrogenated species engaging in C–H bond breaking. Results are generally insensitive to bulk structure and surface facet. Results suggest metal-rich Pd phosphides to have favorable adsorption characteristics for catalytic dehydrogenation, consistent with recent observations.  more » « less
Award ID(s):
1647722
PAR ID:
10431180
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Catalysis Science & Technology
Volume:
12
Issue:
18
ISSN:
2044-4753
Page Range / eLocation ID:
5629 to 5639
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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