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Title: Nano-confinement inside molecular metal oxide clusters: Dynamics and modified encapsulation behavior

Abstract

Encapsulation behavior, as well as the presence of internal catalytically-active sites, has been spurring the applications of a 3 nm hollow spherical metal oxide cluster {Mo 132} as an encapsulation host and a nano-reactor. Due to its well-defined and tunable cluster structures, and nano-scaled internal void space comparable to the volumes of small molecules, this cluster provides a good model to study the dynamics of materials under ultra-confinement. Neutron scattering studies suggest that bulky internal ligands inside the cluster show slower and limited dynamics compared to their counterparts in the bulk state, revealing the rigid nature of the skeleton of the internal ligands. Furthermore, NMR studies indicate that the rigid internal ligands that partially cover the interfacial pore on the molybdenum oxide shells are able to block some large guest molecules from going inside the capsule cluster, which provides a convincing protocol for size-selective encapsulation and separation.

Authors:
ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [1]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Spallation Neutron Source (SNS)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1334460
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Chemistry - A European Journal
Additional Journal Information:
Journal Volume: 22; Journal Issue: 40; Journal ID: ISSN 0947-6539
Publisher:
ChemPubSoc Europe
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY

Citation Formats

Wang, Zhe, Daemen, Luke L., Cheng, Yongqiang, Mamontov, Eugene, Bonnesen, Peter V., Hong, Kunlun, Ramirez-Cuesta, Anibal J., and Yin, Panchao. Nano-confinement inside molecular metal oxide clusters: Dynamics and modified encapsulation behavior. United States: N. p., 2016. Web. doi:10.1002/chem.201603239.
Wang, Zhe, Daemen, Luke L., Cheng, Yongqiang, Mamontov, Eugene, Bonnesen, Peter V., Hong, Kunlun, Ramirez-Cuesta, Anibal J., & Yin, Panchao. Nano-confinement inside molecular metal oxide clusters: Dynamics and modified encapsulation behavior. United States. doi:10.1002/chem.201603239.
Wang, Zhe, Daemen, Luke L., Cheng, Yongqiang, Mamontov, Eugene, Bonnesen, Peter V., Hong, Kunlun, Ramirez-Cuesta, Anibal J., and Yin, Panchao. 2016. "Nano-confinement inside molecular metal oxide clusters: Dynamics and modified encapsulation behavior". United States. doi:10.1002/chem.201603239. https://www.osti.gov/servlets/purl/1334460.
@article{osti_1334460,
title = {Nano-confinement inside molecular metal oxide clusters: Dynamics and modified encapsulation behavior},
author = {Wang, Zhe and Daemen, Luke L. and Cheng, Yongqiang and Mamontov, Eugene and Bonnesen, Peter V. and Hong, Kunlun and Ramirez-Cuesta, Anibal J. and Yin, Panchao},
abstractNote = {Encapsulation behavior, as well as the presence of internal catalytically-active sites, has been spurring the applications of a 3 nm hollow spherical metal oxide cluster {Mo132} as an encapsulation host and a nano-reactor. Due to its well-defined and tunable cluster structures, and nano-scaled internal void space comparable to the volumes of small molecules, this cluster provides a good model to study the dynamics of materials under ultra-confinement. Neutron scattering studies suggest that bulky internal ligands inside the cluster show slower and limited dynamics compared to their counterparts in the bulk state, revealing the rigid nature of the skeleton of the internal ligands. Furthermore, NMR studies indicate that the rigid internal ligands that partially cover the interfacial pore on the molybdenum oxide shells are able to block some large guest molecules from going inside the capsule cluster, which provides a convincing protocol for size-selective encapsulation and separation.},
doi = {10.1002/chem.201603239},
journal = {Chemistry - A European Journal},
number = 40,
volume = 22,
place = {United States},
year = 2016,
month = 8
}

Journal Article:
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