Monolayer Catalyst Design Using Slrr of UPD Monolayers – Fundamental Aspects and Interplay of UPD, Reaction Kinetics, and Nucleation Kinetics

Brankovic, Stanko

The deposition protocol based on surface limited Redox replacement reaction (SLRR) of UPD monolayers [[i]] has gained a lot of attention in recent years. It has been extensively used for preparation of highly active catalysts [[ii],[iii],[iv],[v],[vi],[vii]], and for growth of homo/heteroepitaxial 2D films with arbitrary thickness [[viii],[ix]]. The concept behind this deposition protocol has potential for a wide range of applications, yet very little is known about the governing phenomena determining morphology of deposited catalyst monolayers.

In this talk we will review fundamental relations controlling the catalyst monolayer nucleation as a prelude for its morphology design. The analytical model describing the nucleation density as a function on reaction stoichiometry, rate constant, reaction order, and fundamental parameters describing surface transport will be presented and discussed with reflection to experimental data. We will show the practical relevance of SLRR reaction kinetics on deposition flux and nucleation kinetics of metal/catalyst monolayers. The different approaches for manipulation of the reaction kinetics and thermodynamics will be discussed within the frame of experimental design/protocols to control the morphology of deposited catalyst monolayers. The emphasis will be made on some convenient and yet allowed approximation relevant to the real systems.

In the second part of the talk the spectroscopic data will be presented emphasizing that catalyst morphology i.e. nanocluster size is an important design parameter directly affecting the monolayer catalyst performance. Examples of Pt/Pd(hkl) and Pt/Au(hkl) will be discussed with in the light of the Pt monolayer morphology.

In the last part of the talk we will show the examples of Pb UPD on Pt and Ru modified Au(111) as a prelude to design of the novel 2D catalyst monolayers and nanoclusters configurations.

The authors acknowledge the support from NSF Chemistry division under the contract # 0955922.

[1] SRBrankovic@uh.edu

References:

[i]) S. R. Brankovic, J. X. Wang and R.R. Adzic, Surface Science, 474, L173 (2001).

[ii]) V. M. Brussel, G. Kokkinidis, A. Hubin, C. Buess-Herman, Electrochim. Acta 48, 3909 (2003).

[iii]) J. L. Znahg, M.B. Vukmirovic, Y. Xu, M. Marvikakis, R. R. Adzic, Angewandte Chemie-International Edition, 44, 2132 (2005).

[iv]) J. L. Znahg, M.B. Vukmirovic, K. Sasaki, A. U. Nilekar, M. Marvikakis, R. R. Adzic, J. Am. Chem. Soc., 127, 12480 (2005).

[v]) A. Kongkanand, and S. Kuwabata, J. Phys. Chem. B, 109, 2319 (2005).

[vi]) Y. D. Jin, Y. Shen, and S. J. Dong, J. Phys. Chem. B, 108, 8142, (2004).

[vii]) K. Sasaki, Y. Mo, J. X. Wang, M. Balasubramanian, F. Uribe, J. McBreen, R.R. Adzic, Electrochim. Acta, 48, 3841, (2003).

[viii]) R. Vasilic, L.T. Viyannalage and N. Dimitrov J. Electrochem. Soc., 153, C648, (2006).

[ix]) Y.G. Kim , J.Y. Kim, D. Vairavapandian, J.L. Stickney, J. Phys. Chem. B 110, 17998 (2006)

2014 ECS and SMEQ Joint International Meeting (October 5-9, 2014)

October 05 - 09, 2014

1382
Monolayer Catalyst Design Using Slrr of UPD Monolayers – Fundamental Aspects and Interplay of UPD, Reaction Kinetics, and Nucleation Kinetics

1382 Monolayer Catalyst Design Using Slrr of UPD Monolayers – Fundamental Aspects and Interplay of UPD, Reaction Kinetics, and Nucleation Kinetics

1382
Monolayer Catalyst Design Using Slrr of UPD Monolayers – Fundamental Aspects and Interplay of UPD, Reaction Kinetics, and Nucleation Kinetics