Water Adsorption on Wurtzite GaN Surfaces

ORAL

Abstract

A solid solution of wurtzite GaN/ZnO absorbs light in the visible and can photosplit water.\footnote{K. Maeda, K. Teramura, D. Lu, T. Takata, N. Saito, Y. Inoue, and K. Domen, Nature 440, 295 (2006)} The water is oxidized by the photo-holes at the surface of the semiconductor alloy. However, microscopic details of the oxidation process are unknown. We present a first-principles study of water adsorption on wurtzite GaN. We study the structures and energetics of water adsorption, calculate the energy barrier for water dissociation, analyze the water-water interactions, and study the electronic structure. The results are compared with water adsorption on ZnO surface. We also study the behavior of the holes near the water-semiconductor interface.

Authors

  • Xiao Shen

    • Stony Brook University
  • Philip B. Allen

    • Stony Brook University
  • Mark S. Hybertsen

    • Brookhaven National Laboratory
  • James T. Muckerman

    • Brookhaven National Laboratory