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  • Development of ceria-supported metal-oxide (MOx/CeO2) catalysts via a one-pot chemical vapor deposition (OP-CVD) technique: Structure and reverse water gas shift reaction study
Title: Development of ceria-supported metal-oxide (MOx/CeO2) catalysts via a one-pot chemical vapor deposition (OP-CVD) technique: Structure and reverse water gas shift reaction study
Current synthesis techniques for metal oxide (MOx)-supported catalysts have certain limitations of undesired target loading, ineffective dispersion of active species over the surface, uncontrolled particle size of active species, and complicated synthesis steps. We developed a one-pot chemical vapor deposition (OP-CVD) methodology; by using which a solid metal precursor forms a vapor in a controlled condition and gets supported over the surrounding matrix. The theoretical stability followed by experimental validation using TGA is crucial for selecting the metal precursors. Three simple steps viz. premixing, dispersion, and rapid fixation by calcination are involved in the catalyst development via the OP-CVD approach. This study solely focused on the synthesis of 3d transition MOx over ceria support. The physicochemical characterizations of the prepared catalysts were performed by XRD, ICP-OES, SEM-EDX, CO pulse chemisorption, XANES, and EXAFS analyses to understand the crystal structure of involved species, target metal loading, dispersion, and particle size and prove the feasibility and viability of OP-CVD. The prepared catalysts were further tested for reverse water gas shift (RWGS) reaction to link their structural information with activity. The RWGS reaction data showed that the CO activity and CO selectivity were metal - and metal precursor-dependent. Higher CO activity of > 0.1 mol/h g-cat was observed for Cu and Co-based catalysts, with CO selectivity of ~100 %. This study provides an opportunity to produce effcient supported catalysts in a convenient way, providing effective catalytic activity.  more » « less
Award ID(s):
2050824
PAR ID:
10655945
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Chemical Engineering Journal
Volume:
504
Issue:
C
ISSN:
1385-8947
Page Range / eLocation ID:
158726
Subject(s) / Keyword(s):
Catalysts One-pot chemical vapor deposition Organometallic precursor Monomer Reverse water gas shift reaction Ceria
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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