Small metal nanoparticles (NPs) within the size range of 1-3 nm exhibit unique electronic and catalytic properties.1–3 Thiolated nanoparticles have been shown to undergo an entropically driven redistribution of the capping layer with a Ausurface-AuNP system. It has been postulated that different substrate and NP materials may be employed for surface design.4 The aim of this work was to investigate surface structure modification of different substrate-NP combinations, in alkaline media and via their performance in the electro-catalytic decomposition of glycerol (GlyOH).5 Ptsurface-AuNP and Ausurface-PtNP combinations were investigated, by immersion of the surfaces into solutions of the NPs. AuNPs were synthesised using a bottom-up metal reduction6, and PtNPs were synthesised via the cathodic corrosion method.7,8 Electrochemical responses were measured using cyclic voltammetry (CV).Ptsurface-AuNP resulted in a lower current response, but no change in characteristic Pt peaks within the CV profile, indicating that the AuNPs remain protected by the thiol capping layer on the Pt surface. However, Ausurface-PtNP gave a CV displaying both Au and Pt characteristic peaks (Fig. 1), suggesting there is thiol surface diffusion from the PtNPs into the bulk.1 S. Hrapovic, Y. Liu, K. B. Male and J. H. T. Luong, Anal. Chem., 2004, 76, 1083–1088.2 R. Narayanan and M. A. El-Sayed, Nano Lett., 2004, 4, 1343–1348.3 T. Albrecht, S. F. L. Mertens and J. Ulstrup, J. Am. Chem. Soc., 2007, 129, 9162–9167.4 E. Pensa and T. Albrecht, J. Phys. Chem. Lett., 2018, 9, 57–62.5 J. Monzó, Y. Malewski, F. J. Vidal-Iglesias, J. Solla-Gullon and P. Rodriguez, ChemElectroChem, 2015, 2, 958–962.6 H. Qian and R. Jin, Chem. Mater., 2011, 23, 2209–2217.7 A. I. Yanson, P. Rodriguez, N. Garcia-Araez, R. V Mom, F. D. Tichelaar and M. T. M. Koper, Angew. Chemie Int. Ed., 2011, 50, 6346–6350.8 A. I. Yanson, P. V Antonov, P. Rodriguez and M. T. M. Koper, Electrochim. Acta, 2013, 112, 913–918. Figure 1