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 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 29 Issue: 12
  • Publication Date: 2017
  • Doi Number: 10.1088/1361-648x/aa57e3
  • Title of Journal : JOURNAL OF PHYSICS-CONDENSED MATTER
  • 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

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.