Optical Properties of Nanocrystal Interfaces in Compressed MgO Nanopowders

Mckenna KP, Koller D, Sternig A, Siedl N, Govind N, Sushko PV, Diwald O (2011)

Publication Type: Journal article

Publication year: 2011

Journal

ACS nano American Chemical Society

Book Volume: 5

Pages Range: 3003-3009

Journal Issue: 4

DOI: 10.1021/nn200062d

Abstract

The optical properties and charge trapping phenomena observed on oxide nanocrystal ensembles can be strongly influenced by the presence of nanocrystal interfaces. MgO powders represent a convenient system to study these effects due to the well-defined shape and controllable size distributions of MgO nanocrystals. The spectroscopic properties of nanocrystal interfaces are investigated by monitoring the dependence of absorption characteristics on the concentration of the interfaces in the nanopowders. The presence of interfaces is found to affect the absorption spectra of nanopowders more significantly than changing the size of the constituent nanocrystals and, thus, leading to the variation of the relative abundance of light-absorbing surface structures. We find a strong absorption band in the 4.0$-$5.5 eV energy range, which was previously attributed to surface features of individual nanocrystals, such as corners and edges. These findings are supported by complementary first-principles calculations. The possibility to directly address such interfaces by tuning the energy of excitation may provide new means for functionalization and chemical activation of nanostructures and can help improve performance and reliability for many nanopowder applications.

Authors with CRIS profile

Andreas Sternig Lehrstuhl für Feststoff- und Grenzflächenverfahrenstechnik Nicolas Siedl Lehrstuhl für Feststoff- und Grenzflächenverfahrenstechnik Oliver Diwald Lehrstuhl für Feststoff- und Grenzflächenverfahrenstechnik

Additional Organisation(s)

Exzellenz-Cluster Engineering of Advanced Materials

Involved external institutions

Tohoku University JP Japan (JP) Technische Universität Wien / Vienna University of Technology AT Austria (AT) University College London (UCL) GB United Kingdom (GB) Pacific Northwest National Laboratory US United States (USA) (US)

How to cite

APA:

Mckenna, K.P., Koller, D., Sternig, A., Siedl, N., Govind, N., Sushko, P.V., & Diwald, O. (2011). Optical Properties of Nanocrystal Interfaces in Compressed MgO Nanopowders. ACS nano, 5(4), 3003-3009. https://dx.doi.org/10.1021/nn200062d

MLA:

Mckenna, Keith P., et al. "Optical Properties of Nanocrystal Interfaces in Compressed MgO Nanopowders." ACS nano 5.4 (2011): 3003-3009.

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