Image of the Month

May 2016

Double-Stranded Water on Stepped Platinum Surfaces

Figure 1: Atomic positions obtained by density functional calculations overlaid on an image created by a scanning tunneling microscope of D2O-covered step edges on Pt(553). STM image of D2O-covered step edges on Pt(553) [Tip type: cut and pull Pt/Ir; 4.5×4.5nm2; TSTM=25K; V=−1V , I= −9pA (Phys. Rev. Lett. 116, 136101)

The interaction of platinum with water plays a key role in (electro)catalysis. Herein, we describe a combined theoretical and experimental study that resolves the preferred adsorption structure of water wetting the Pt(111)-step type with adjacent (111) terraces. Double stranded lines wet the step edge forming water tetragons with dissimilar hydrogen bonds within and between the lines. Our results qualitatively explain experimental observations of water desorption and impact our thinking of solvation at the Pt electrochemical interface.

Credits:
Manuel J. Kolb1, Rachael G. Farber2, Jonathan Derouin2, Cansin Badan1, Federico Calle-Vallejo1, Ludo B. F. Juurlink1, Daniel R. Killelea2, and Marc T. M. Koper1 (Phys. Rev. Lett. 116, 136101)

1 Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA, Leiden, The Netherlands

2 Department of Chemistry and Biochemistry, Loyola University Chicago, Chicago, Illinois 60660, USA

Images and data graciously provided by Dan Killelea, Loyola University Chicago, Chicago, Illinois.

Microscope:
RHK PanScan Freedom Microscope

Control System:
RHK R9 Control System