Characterization of Bulk Structure in Zinc Orthotitanate: A Density Functional Theory and EXAFS Investigation

Abstract

Development of high‐efficiency multicontaminant sorbents is critical for commercialization of power plants utilizing integrated gasification combined cycle technologies. A known prototypical sorbent for this application is the compound zinc orthotitanate, Zn2TiO4 (ZTO). Previous work has not completely resolved the atomic‐level structure of ZTO. Results from both experimental X‐ray absorption fine structure measurements and density functional theory (DFT) calculations are presented and are in quantitative agreement. The DFT calculations identify the octahedral site occupation of Zn and Ti atoms that give the lowest energy ground state structure. We have supplemented our DFT calculations with a cluster expansion model used to parameterize Monte Carlo (MC) simulations. The results of the MC simulations reveal the temperature dependence of the equilibrium octahedral site occupation in Zn2TiO4.

DFT characterization of adsorption and diffusion mechanisms of H, As, S, and Se on the zinc orthotitanate(010) surface

“…This cation distribution was an unknown component of the atomic structure of bulk ZTO based on extant experimental results from the literature [22]. We showed recently that the bulk structure predicted by our calculations is consistent with EXAFS characterization of ZTO [2].…”

“…In our calculations, we used the low energy ZTO(0 1 0) slab previously identified from DFT calculations [2,3]. This ZTO(0 1 0) surface termination was found to be the lowest energy ZTO surface by about 0.08 J/m 2 in our previous work [3].…”

“…The broad goal of our recent work has been to begin developing a detailed understanding of existing sorbent materials for contaminant cleanup in syngas [2,3]. In this paper, we use density functional theory (DFT) to study the mechanism of the uptake of S, H, As and Se by the regenerable sorbent material zinc orthotitanate (ZTO), Zn 2 TiO 4 [4][5][6][7][8][9][10][11].…”

R.F. and microwave dielectric properties of (Zn0.95M0.05)2TiO4 (M=Mn2+, Co2+, Ni2+ or Cu2+) ceramics

“…and microwave dielectric properties. Although, Zn 2 TiO 4 per se has not been very attractive as a microwave dielectric resonator material, nevertheless its low sintering temperature (∼1100 ± 100 • C) and flexibility to allow dilute substitution [8,11,12] hold the possibility of making this system attractive to be explored for LTCC applications.…”

Synthesis and characterization of Eu3+, Ti4+@ ZnO organosols and nanocrystalline c-ZnTiO3thin films aiming at high transparency and luminescence

“…According to literature, several phases, including α-Zn 2 TiO 4 (cubic, Fd3m) [26], h-ZnTiO 3 (hexagonal, R3) [27], c-ZnTiO 3 (cubic) [28][29][30] or Zn 2 Ti 3 O 8 (cubic) [31] exist in the phase diagram of the ZnO-TiO 2 system. Whereas the first two phases are well identified and characterized, there are many contradictions for the last two cation-deficient spinel-type structures [31].…”