Structural and electronic properties of bulk and low-index surfaces of zincblende PtC

Sensoy M. G., Toffoli D., TOFFOLİ H.

JOURNAL OF PHYSICS-CONDENSED MATTER, vol.29, no.12, 2017 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 29 Issue: 12
  • Publication Date: 2017
  • Doi Number: 10.1088/1361-648x/aa57e3
  • Journal Name: JOURNAL OF PHYSICS-CONDENSED MATTER
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Keywords: platinum carbide, density functional theory, workfunction, catalysis, surface adsorption, TRANSITION-METAL CARBIDES, HIGH-PRESSURE, 1ST-PRINCIPLES CALCULATIONS, TUNGSTEN CARBIDE, HIGH-TEMPERATURE, 1ST PRINCIPLES, PLATINUM, GAS, OXIDATION, OXYGEN
  • Middle East Technical University Affiliated: Yes

Abstract

Transition metal carbides have been extensively used in diverse applications over the past decade. Their versatility is in part thanks to their unique bonding, which displays a mixture of ionic, metallic and covalent character. While the bulk structure of zincblende (ZB) PtC has been investigated several times, a detailed understanding of the electronic and structural properties of its low-index surfaces is lacking. In this work, we present an ab initio investigation of the properties of five crystallographic ZB PtC surfaces (Pt/C-terminated PtC(100), PtC(110) and Pt/C-terminated PtC(111)). Upon geometry optimization, both polar and nonpolar surfaces undergo a mild interlayer relaxation, without extensive reconstructions. Calculated vacancy formation energies indicate facile C removal on the (111) surface while Pt-vacancy formation is endothermic. Finally, atomic O adsorption energies on all surfaces reveal a high affinity of the C-terminated surfaces towards this species.