Defects are ubiquitous in materials, and can fundamentally alter their chemical, optical, thermal and electronic properties. In particular, point defects can impact both ground-state and excited-state properties, as well as the material’s response to external fields and stimuli. Recent technical advancements highlight the important role that defects play in engineering new functional materials. For example, recent intensive efforts have demonstrated that otherwise inert transition metal oxide materials can become (photo-)electrochemically active through the dynamic variation of the oxygen defect concentration and distribution. Similarly, designing and engineering defect groups and networks have opened compelling paths to tuning the electronic, optical and physiochemical properties of transition-metal dichalcogenide and other two-dimensional layered materials. However, harnessing functional defects in materials presents an outstanding scientific and technical challenge to researchers; new effective and efficient theoretical and experimental tools are needed to help rationalize, predict, observe, visualize and control defect formation, migration and interactions. These techniques are largely limited or in some cases unavailable at present.
To address the pressing opportunities and challenges, we have designed this symposium to highlight the recent trends in the design, synthesis and characterization of functional defects. The symposium will bridge expertise in theoretical modeling/simulation, materials synthesis, functional measurement/control, and advanced characterization. Particular attention will be paid to high-throughout combinatorial investigations, predictive modeling of defect physics and chemistry, and the synthesis, control, and characterization of functional defects in energy materials, which may include but not limited to solid oxide fuel cells, proton conducting fuel cells, electrocatalysis, thermoelectric, solid state lighting, transparent conducting oxides, photovoltaics and solid state batteries. This topic may also include novel architectures for studying defects, such as the use of epitaxial heterostructures. Also of interest are, in-situ monitoring of functional defect formation/migration/ordering, the interplay between defect responses in ionic lattices and their manipulation by external fields, and use of transformative imaging capabilities to probe defect-driven phenomena in-situ along with their dynamics. This symposium will provide an interactive forum for scientists from various fields interested in the application of defect engineering to both classical and emerging applications. Specific sessions will be organized based on scientific theme topics in order to foster cross-fertilization of ideas and strategies. There will be sessions with a focus on recent methodological advances in studying point and extended defects in functional materials. This symposium aims to benefit materials scientists from various backgrounds, and will help encourage the implementation of predictive design, smart synthesis/control and advanced characterization approaches to solve the needed problems in this field.