Unveiling the Hidden Influence of Defects via Experiment and Data Science
Unveiling the Hidden Influence of Defects via Experiment and Data Science
复制标题
通过实验和数据科学揭示缺陷的隐藏影响
DOI:
10.1021/acs.chemmater.3c01817
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发表时间:
2023
影响因子:
8.6
通讯作者:
Brgoch, Jakoah
中科院分区:
文献类型:
--
作者:
Sambur, Justin;Brgoch, Jakoah
The elephant in the room of materials chemistry is that all materials inherently have defects and impurities. Defects can tremendously influence a material’s functional properties by deteriorating the performance in some samples, enhancing performance in others, or occasionally contributing to entirely new functionality. A classic example is the presence of intrinsic surface oxygen vacancies (defects) on metal oxide photocatalysts such as TiO2. 1− 3 These surface oxygen vacancies are vital for effectively binding reactant molecules and facilitating charge transfer, boosting activity. 2, 4 Similar charge trapping defects also enable applications in luminescent materials. 5 Persistent luminescence phosphors, for example, require the same defects to trap electrons in the excited state, which are eventually slowly released through thermal activation. This defect-related emission process gives rise to the famous glowin-the-dark property of SrAl 2O4: Eu2+, Dy3+ found in emergency signs and children’s toys. 6, 7 Mitigating these same defects in phosphors enables their application in LED lighting and display applications. 8 Targeting and controlling specific (point) defect formation and concentrations is clearly indispensable for obtaining desired functionalities. Unfortunately, unless defects are the focus of a research project, most scientists and engineers gloss over their impact for one main reason they are incredibly difficult to identify, characterize, and understand how they contribute to ensemblelevel sample properties. In this editorial, we highlight this “defect challenge”, emphasizing that it can only be solved through a cross-cutting research effort supported by computational and experimentalists alike. It will require new techniques in high-throughput computing, data science, and, most importantly, spectroscopy at the single-particle level. Further adopting FAIR (Findable, Accessible, Interoperable, and Reusable) principles 9 and thinking about how large data sets are shared and archived will play a vital role in making use of ultrarich (in information and actual costs) data sets that are currently being under-utilized. Significant effort is going into establishing new approaches to study defects with the hope of closing this gap. Developments in computational modeling have started to unlock a fundamental understanding of how defects influence a material’s properties. Density functional theory (DFT), for example, has provided insight into the defect energy levels and their role in semiconducting and insulating materials like SrAl2O4: Eu2+ to understand how intrinsic defects enable its famous persistent luminescence. 10 Advanced computational methods have since been developed to more accurately represent the local structure of materials containing point defects, ensuring the lowest energy geometries are modeled. 11 Similar progress has been made in considering multiple defects, defect clustering, and defect dynamics, 12, 13 while machine learning force fields in molecular dynamics are gaining popularity for capturing the materials chemistry of larger systems, although the ability for molecular dynamics (MD) to capture defect physics is still limited. Efforts to automate this computational process are also furthering the ability to study the impact of defects on an array of systems, leading to new crystal− chemical connections that can be used to manipulate a material’s physical properties. One setback, however, is that these calculations require computationally expensive hybrid functionals to account for charge localization, making it intractable to perform these calculations on a diverse number of systems. Despite this reality, there is still potential for tremendous impact as …
影响因子:
8.6
作者:
Christopher Linderälv;D. Åberg;P. Erhart
通讯作者:
P. Erhart