Tetrahexahedral nanocrystals (THH NCs) of fcc metals such as Pt, Pd, Rh possess a high catalytic activity due to their open surface structure and high surface energy.¹ It has been determined that the THH Pt NCs are enclosed by {hk0} facets that can be decomposed with different subfacets. As an example, the most frequently prepared THH Pt NCs are bounded with {730} facets, which can be decomposed into (310) + 2(210) or 3(100)´(110) + 2(100)´(110) + 2(100)´(110). ^1,2 It is obvious that the high catalytic activity of the THH Pt NCs originates from the high density of surface active sites.

In the current study through applying cyclic voltammetry (CV) and in situ FTIR spectroscopy, CO adsorption and oxidation were used as probe reactions to investigate the surface sites on THH Pt NCs, in order to understand their role in practical electrocatalysis. Furthermore, the electrocatalytic property towards small organic fuel molecule oxidation of sub-monolayer of adatoms as Bi, Ru and Au on THH Pt NCs, and multi Pt atomic layer on THH Pd NCs were studied to gain knowledge on surface structure effects of high-index faceted nanocrystals in electrocatalysis.

Acknowledgement: This work was supported by Natural Science Foundation of China (21573183, 21621091).

References:

1. Tian et al. Science, 2007, 316, 732-735.
2. Hermann, “Crystallography and Surface Structure, an introduction for surface scientists and nanoscientists”, Wiley-VCH, Berlin 2011, ISBN 978-3-527-41012-5.
3. S. Chen et al. J. Am. Chem. Soc. 2011, 133, 12930.
4. X. Liu et al. ACS Catalysis, 2012, 2, 708.
5. X. Liu et al. PCCP, 2012, 14, 16415.
6. X. Liu et al. Faraday Discuss. 2014, 176, 409.
7. F. Lin et al, Chem. Sci., 2017, submitted