Water dissociates at the aqueous interface with reduced anatase TiO2(101)

DOI: 10.1021/acs.jpclett.8b01182

Authors: Immad M. Nadeem (University College London; Diamond Light Source) , Jon P. W. Treacy (The University of Manchester) , Sencer Selcuk (Princeton University) , Xavier Torrelles (Institut de Ciència de Materials de Barcelona (CSIC)) , Hadeel Hussain (The University of Manchester) , Axel Wilson (University College London) , David C. Grinter (University College London) , Gregory Cabailh (Sorbonne Université, CNRS) , Oier Bikondoa (University of Warwick; ESRF, The European Synchrotron) , Chris Nicklin (Diamond Light Source) , Annabella Selloni (Princeton University) , Jorg Zegenhagen (Diamond Light Source) , Robert Lindsay (The University of Manchester) , Geoff Thornton (University College London)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: The Journal Of Physical Chemistry Letters

State: Published (Approved)
Published: May 2018
Diamond Proposal Number(s): 8634 , 11345

Abstract: Elucidating the structure of the interface between natural (reduced) anatase TiO2 (101) and water is an essential step towards understanding the associated photo-assisted water splitting mechanism. Here we present surface X-ray diffraction results for the room temperature interface with ultra-thin and bulk water, which we explain by reference to density functional theory calculations. We find that both interfaces contain a 25:75 mixture of molecular H2O and terminal OH bound to titanium atoms along with bridging OH species in the contact layer. This is in complete contrast to the inert character of room temperature anatase TiO2 (101) in ultra-high vacuum. A key difference between the ultra-thin and bulk water interfaces is that in the latter, water in the second layer is also ordered. These molecules are hydrogen bonded to the contact layer, modifying the bond angles.

Journal Keywords: Interfaces; Oxides; Adsorption; Layers; Ultrahigh vacuum

Subject Areas: Chemistry, Materials, Physics


Instruments: I07-Surface & interface diffraction

Added On: 22/05/2018 12:03

Documents:
acs.jp4545lett.pdf

Discipline Tags:

Surfaces Physics Physical Chemistry Chemistry Materials Science interfaces and thin films

Technical Tags:

Diffraction