On the Origin of Sinter‐Resistance and Catalyst Accessibility in Raspberry‐Colloid‐Templated Catalyst Design
- Department of Chemistry and Chemical Biology Harvard University Cambridge MA 02138 USA, Harvard John A. Paulson School of Engineering and Applied Sciences Harvard University Cambridge MA 02138 USA
- Center for Nanoscale Systems Harvard University Cambridge MA 02138 USA
- Harvard John A. Paulson School of Engineering and Applied Sciences Harvard University Cambridge MA 02138 USA
- Department of Mechanical Engineering Northwestern University Evanston IL 60208 USA
- Harvard John A. Paulson School of Engineering and Applied Sciences Harvard University Cambridge MA 02138 USA, Computational Research Division Lawrence Berkeley Laboratory Berkeley CA 94720 USA
- Harvard John A. Paulson School of Engineering and Applied Sciences Harvard University Cambridge MA 02138 USA, Center for Nanoscale Systems Harvard University Cambridge MA 02138 USA
Nanoparticle (NP) sintering is a major cause of the deactivation of supported catalysts. Raspberry‐colloid‐templated (RCT) catalysts are an emerging class of materials that show an unprecedented level of sinter‐resistance and exhibit high catalytic activity. Here a comprehensive study of the origin of NP stability and accessibility in RCT catalysts using theoretical modeling, 3D electron microscopy, and epitaxial overgrowth is reported. The approach is showcased for silica‐based RCT catalysts containing dilute Pd‐in‐Au NPs previously used in hydrogenation and oxidation catalysis. Modeling of the contact line of the silica precursor infiltrating into the assembled raspberry colloids suggests that a large part of the particles must be embedded into silica, which is confirmed by quantitative visualization of >200 individual NPs by dual‐axis electron tomography. The RCT catalysts have a unique structure in which all NPs reside at the pore wall but have >50% of their surface embedded in the matrix, giving rise to the strongly enhanced thermal and mechanical stability. Importantly, epitaxial overgrowth of Ag on the supported NPs reveals that not only the NP surface exposed to the pore but the embedded interface as well remained chemically accessible. This mechanistic understanding provides valuable guidance in the design of stable catalytic materials.
- Research Organization:
- Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
- Sponsoring Organization:
- National Science Foundation (NSF); USDOE; USDOE Office of Science (SC), Basic Energy Sciences (BES)
- Grant/Contract Number:
- AC02-05CH11231; SC0012573
- OSTI ID:
- 1818828
- Alternate ID(s):
- OSTI ID: 1818829
OSTI ID: 1825003
- Journal Information:
- Advanced Functional Materials, Journal Name: Advanced Functional Materials Journal Issue: 49 Vol. 31; ISSN 1616-301X
- Publisher:
- Wiley Blackwell (John Wiley & Sons)Copyright Statement
- Country of Publication:
- Germany
- Language:
- English