Correction: Modeling composite electrolytes for low-temperature solid oxide fuel cell application: structural, vibrational and electronic features of carbonate–oxide interfaces

Abstract

Correction for ‘Modeling composite electrolytes for low-temperature solid oxide fuel cell application: structural, vibrational and electronic features of carbonate–oxide interfaces’ by Chiara Ricca et al., J. Mater. Chem. A, 2016, DOI: 10.1039/c6ta06827h.

On the Stability Issues of TiO2-Based Composites in View of Fuel Cell Application: A Combined Experimental and Theoretical Investigation

“…This resulted in a large cell parameter mismatch between the two building blocks (δ a = 3.0% and δ b = 51.0%). Similar to the YSZ−LiKCO 3 composite previously investigated, 6,14,16 large supercell models of the two surfaces ((4 × 4) for LiKCO 3 -(001) and (2 × 2) for TiO 2 -(101)) were built, and the carbonate slab was rotated along the normal to the oxide surface plane in order to reorient the CO 3 groups toward the Ti surface sites since these moieties can reasonably be expected to be responsible for the binding of the carbonate to the oxide. Based on the stoichiometry of each phase and the neutrality of the whole system, an interface model with a P1 symmetry and 180 atoms was selected, 60 atoms (Li 10 K 10 (CO 3 ) 10 ) belonging to the 5 layers of the carbonate To study Li intercalation, neutral interstitial Li atoms (Li i ) were introduced in the optimized unit cell describing the oxide−carbonate interface that, with a minimum distance between periodically repeated images of the defect of ∼7.5 Å, was found to be sufficient to avoid spurious interactions between each defect and its periodic images.…”

“…This combined approach was designed and validated on YSZ–LiKCO 3 materials ,,, and described in detail in previous works. , It is based on the very close analogy existing between the steps found during the synthesis procedure and those involved in the computational approach proposed to simulate the composite material, which requires studying the bulk and surfaces of each phase separately before building a proper interface model. The strong interplay between theoretical results (microscopic level) and experimental data (macroscopic level) make the proposed combined approach particularly appealing for the investigation of the properties of composite materials as SOFC electrolytes.…”

“…At the same time, modeling may help experimentalists rationalizing their results by making predictions and ultimately enhancing the understanding of the electrochemical processes and mechanisms involved: while there is a lack of analytical tools that can investigate the interfacial effects directly, 15 theoretical studies can indeed provide a direct picture of the interfaces as well as information on the interfacial effects at the atomic level. This combined approach was designed and validated on YSZ−LiKCO 3 materials 6,14,16,17 and described in detail in previous works. 6,14 It is based on the very close analogy existing between the steps found during the synthesis procedure and those involved in the computational approach proposed to simulate the composite material, which requires studying the bulk and surfaces of each phase separately before building a proper interface model.…”

Conduction Mechanisms in Oxide–Carbonate Electrolytes for SOFC: Highlighting the Role of the Interface from First-Principles Modeling

“…The two-dimensional periodic interface model used to investigate the conduction mechanisms in these composite materials is taken from ref : the unit cell of the YSZ–LiKCO 3 interface has P 1 symmetry with cell parameters a = 7.17 Å, b = 6.27 Å, and γ = 90.10° and contains 106 atoms, 36 (Li 6 K 6 (CO 3 ) 6 ) belonging to the 3 layers of the carbonate phase and 72 (Zr 20 Y 4 O 46 ) organized in 6 O–Zr/Y–O layers along the c -axis for YSZ. It was built starting from models of the oxide and carbonate most stable surfaces that were previously found to ensure convergence of the structure.…”

“…Dealing with these two phase systems and providing an accurate and reliable description of their properties can however be challenging, even from the modeling viewpoint, because it requires a careful choice of the methodology and of the models used. To shed some light on these points, we have carried out a detailed theoretical investigation using first-principle methods based on density functional theory (DFT) and a previously proposed YSZ–LiKCO 3 interface model, which has been developed and validated by a combined theoretical and experimental protocol. − In particular, our DFT simulations of the transport mechanisms of Li, O, and proton-related defects provide balanced descriptions, which, albeit issued from a modeling study, allow for the first time for a direct comparison of all major phenomena involved. Furthermore, our study provides valuable hints to experimentalists on the physics and chemistry underpinning the enhancement behavior observed and provides some guidelines to further improve it.…”