@article{be9815b793e6494d83d4a7480886538b,
title = "Direct Visualization of Independent Ta Centers Supported on Two-Dimensional TiO2 Nanosheets",
abstract = "Highly dispersed, supported oxides are ubiquitous solid catalysts but can be challenging to characterize with atomic precision. Here, it is shown that crystalline anatase TiO2 nanosheets ({\^a} ¼5 nm thick) are ideal supports for imaging highly dispersed active sites. Ta cations were deposited by several routes, and high-resolution high angle annular dark-field scanning transmission electron microscopy was used to determine the location of Ta with respect to the TiO2 lattice and quantify Ta-Ta distances. In the best case, it is shown that >80% of Ta atoms are isolated from one another, whereas other techniques are blind to this critical catalytic property or give only qualitative estimates. TiO2 nanosheets may prove to be a useful platform for other types of catalysis studies.",
keywords = "HAADF STEM, microscopy, oxides, single atom catalysts, supported catalysts",
author = "Zhenyu Bo and Thornburg, {Nicholas E.} and Lingxuan Peng and {Gutierrez Moreno}, {Jose Julio} and Michael Nolan and Marks, {Laurence D.} and Notestein, {Justin M.}",
note = "Funding Information: J.J.G.M. and M.N. acknowledge support from the Irish Environmental Protection Agency UisceSense project (W-2015-MS-21) and the SFI-NSF-DEL US Ireland R&D Partnership Program, Grant SFI US/14/e2915 and access to computational resources through the Irish Center for High End Computing.*%blankline%* Funding Information: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Science, under Award DOE DE-FG02-03ER15457 to the Institute for Catalysis for Energy Processes (ICEP) at Northwestern University. This work was supported by the Materials Research Center (MRSEC) at Northwestern University with Grant DMR-112126. N.E.T. and J.M.N. acknowledge financial support from the Dow Chemical Company. This work made use of the EPIC facility of the NUANCE Center at Northwestern University, which has received support from the Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF NNCI-1542205); the MRSEC program (NSF DMR-112126) at the Materials Research Center; the International Institute for Nanotechnology (IIN); the Keck Foundation; and the State of Illinois, through the IIN. This work made use of the JEOL JEM-ARM200CF in the Electron Microscopy Service [Research Resources Center, University of Illinois at Chicago (UIC)]. J.J.G.M. and M.N. acknowledge support from the Irish Environmental Protection Agency UisceSense project (W-2015-MS-21) and the SFI-NSF-DEL US Ireland R&D Partnership Program, Grant SFI US/14/e2915 and access to computational resources through the Irish Center for High End Computing. We acknowledge supply of raw materials (TiO 2 nanosheets) by Dr. Kevin Schwartzenberg (Northwestern University) and atomic layer deposition work by Cassie George (Northwestern University). Publisher Copyright: Copyright {\textcopyright} 2019 American Chemical Society.",
year = "2019",
month = nov,
day = "13",
doi = "10.1021/acs.nanolett.9b03305",
language = "English (US)",
volume = "19",
pages = "8103--8108",
journal = "Nano letters",
issn = "1530-6984",
publisher = "American Chemical Society",
number = "11",
}