论文标题
合金氧化物中键能的键协同模型
Bond Synergy Model for Bond Energies in Alloy Oxides
论文作者
论文摘要
在这项工作中，我们基于纯相键能和键协同因子引入了合金氧化物的金属氧化物键 - 能量模型，这些模型描述了合金对阳离子和氧气之间的键能的影响，这是理解被动膜的形成和稳定性的重要数量。该模型使用密度功能理论能量对二元阳离子合金氧化物进行参数化，并被证明可直接转移到多组分合金氧化物中。我们用金属阳离子为合金氧化物能量的模型参数构成了抗腐蚀合金的基础，包括Fe，Ni，Ni，Cr，Mo，Mo，Mn，Mn，W，Co和Ru。我们发现，等电溶质允许量化氧化物中的纯相键能，并且与共同经验相比，计算出的键能值可提供明智的结果，包括Cr作为Fe-Ni-Cr合金中的被动层层的作用，用于腐蚀应用中。此外，键协同因子可以深入了解合金对阳离子氧键的相互加强和弱化作用，并且可能与混合和电荷中性限制的焓有关。我们证明了如何通过氧化可以识别和实现电荷中立性指出，不同的阳离子取决于合金组成和缺陷的存在。
In this work we introduce a metal-oxide bond-energy model for alloy oxides based on pure-phase bond energies and bond synergy factors that describe the effect of alloying on the bond energy between cations and oxygen, an important quantity to understand formation and stability of passive films. This model is parameterized for binary cation-alloy oxides using density-functional theory energies and is shown to be directly transferable to multi-component alloy oxides. We parameterized the model for alloy oxide energies with metal cations that form the basis of corrosion resistant alloys, including Fe, Ni, Cr, Mo, Mn, W, Co, and Ru. We find that isoelectronic solutes allow quantification of pure-phase bond energies in oxides and that the calculated bond energy values give sensible results compared to common experience, including the role of Cr as the passive-layer former in Fe-Ni-Cr alloys for corrosion applications. Additionally, the bond synergy factors give insights into the mutual strengthening and weakening effects of alloying on cation-oxygen bonds and can be related to enthalpy of mixing and charge neutrality constraints. We demonstrate how charge neutrality can be identified and achieved by the oxidation states that the different cations assume depending on alloy composition and the presence of defects.
