Hydration Structure of Brookite TiO2 (210)

Research output: Contribution to journalArticleScientificpeer-review

Researchers

  • Eero Holmström
  • Simiam Ghan
  • Hitoshi Asakawa
  • Yasuhiro Fujita
  • Takeshi Fukuma
  • Sunao Kamimura
  • Teruhisa Ohno
  • Adam Foster

Research units

  • Kanazawa University
  • Kyushu Institute of Technology
  • Japan Science and Technology Agency

Abstract

The interface of TiO2 and water has been heavily researched due to the photocatalytical capabilities of this system. Whereas the majority of existing work has targeted the rutile and anatase phases of TiO2, much less is known about the brookite phase. In this work, we use first-principles molecular dynamics simulations to find the hydration structure of the brookite (210) surface. We find both pure water and an aqueous solution of KCl to order laterally at the sites of surface Ti cations due to electrostatic and chemical considerations, qualitatively in agreement with experimental high-resolution atomic force microscopy measurements. A significant fraction of surface oxygens is hydroxylated for all cases, with up to 40% realized for the aqueous solution at bulk coverage, a result originating in orientational constraints placed on water near the solvated K and Cl ions. Proton transfer is nearly equally frequent between the surface and liquid regions and within the liquid region, but the presence of K and Cl ions makes proton transfer less efficient.

Details

Original languageEnglish
Pages (from-to)20790-20801
Number of pages12
JournalJournal of Physical Chemistry C
Volume121
Issue number38
Publication statusPublished - 28 Sep 2017
MoE publication typeA1 Journal article-refereed

ID: 15781937