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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.
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This content will become publicly available on August 27, 2026
Single Metal Atom Catalysts Prepared by Diluted Atomic Layer Deposition
The scalable and facile preparation of single-atom catalysts remains a critical challenge. Here, we introduce Diluted Atomic Layer Deposition (DALD), a unique approach for synthesizing supported metal catalysts with precisely tunable loadings. Unlike conventional metal deposition by ALD which uses pure metal precursors, DALD employs a diluted precursor mixture, combining organometallic precursors with the corresponding free ligand in controlled ratios. The method enables precise control over metal loadings, allowing the synthesis of structures ranging from nanoparticles to isolated single atoms, as exemplified by Ir, Rh, and Pt on high-surface-area γ-Al2O3. With its inherent simplicity and exceptional efficiency in metal precursor utilization, DALD represents a highly scalable strategy, unlocking opportunities for integrating single-atom catalysts into industrial processes.
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- PAR ID:
- 10636366
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Applied Materials & Interfaces
- Volume:
- 17
- Issue:
- 34
- ISSN:
- 1944-8244
- Page Range / eLocation ID:
- 48279 to 48289
- Subject(s) / Keyword(s):
- Single Atom Catalysts, Atomic Layer Deposition, Aluminum Oxide, Platinum, Rhodium, Iridium
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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