Energetic and Electronic Properties of P Doping at the Rutile TiO₂ (110) Surface from First Principles

Abstract

Abstract:The energetic and electronic properties of various P doping configurations at the rutile TiO 2 (110) surface are investigated by first-principles density functional theory (DFT) calculations. Several substitution and adsorption configurations for P impurities at the surface and the subsurface are considered. The stability of the P-doped systems is compared on the basis of the calculated formation energy and adsorption energy. Our calculated results indicate that the P impurities replace surface Ti atoms preferentially under O-rich growth conditions，and surface O atoms under Ti-rich conditions. In addition, it was found that the creation of oxygen vacancies favors P incorporation at substitution sites but not at adsorption sites. Doping with a single P atom into an O site may lead to either anionic or cationic states in the dopant.This causes either band-to-band transitions or introduces gap states to band transitions, with the former corresponding to a small band gap narrowing or broadening and the latter resulting in obvious reductions of photon transition energy. Substitutional replacement of Ti atoms by P atoms and adsorption on the surface (P-cation doping) 1 This document is the Accepted Manuscript version of a Published Work that appeared in final form in ournal of Physical Chemistry C, 113 : 9423-9430, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://dx.doi.org/10.1021/jp9016135 results in either a small band reduction or a slight band gap enlargement, depending on the doping sites. It is speculated that the interaction between P impurities and surface oxygen vacancies will lead to further enhanced photocatalytic activity in the visible light region.

Review of First-Principles Studies of TiO2: Nanocluster, Bulk, and Material Interface

“…This is well consistent with the experiment, in which the higher nitrogen concentration does not lead to further optical energy-gap narrowing but makes the growth of N-doped TiO 2 more difficult [85]. In addition, nonmetal doping (C, S, and P) can lower the formation energy of oxygen vacancy [38,[93][94][95], and thus the combined effects of the oxygen vacancy and nonmetal doping cannot be excluded to be responsible for the visible light absorption in N-(C-, S-, and P-) doped TiO 2 .…”

Recent advances in TiO2‐based catalysts for N2 reduction reaction

“…For P‐doped TiO 2 , P valence state is pentavalent in TiO 2 by replacing part of Ti 4+ , which gives rise to OV on the surface and P 3p impurity states, effectively adjusting the electronic structure of TiO 2 69 . Zhao et al .…”

Review of the Structural Stability, Electronic and Magnetic Properties of Nonmetal-Doped TiO$_2$ from First-Principles Calculations

“…[15] This is well consistent with the experiment, in which the higher nitrogen-concentration does not lead to further optical energy-gap narrowing but makes the growth of N-doped TiO 2 more difficult. [49] In addition, nonmetal doping (C, S and P) can lower the formation energy of oxygen vacancy, [11,[57][58][59] and thus the combined effects of the oxygen vacancy and nonmetal doping cannot be excluded to be responsible for the visible-light absorption in N-(C-, S-and P-)doped TiO 2 .…”