This talk will consider new research fields with the first papers from either 2021 or 2022. I will illustrate opportunities for the next 5 to 20 years, some for basic science and some for application.
The common theme is that I will discuss new microstructural tools or new processing methods to get completely new properties.
Dislocations in polycrystalline and single-crystal ceramics are usually present in very low density. However, they are appealing as they are typically charged and can be used both as paths as well as barriers for electric current, they can pin domain walls [1] and can be scattering centers. A special advantage of using dislocations to 1-dimensionally dope ceramics lies in the fact that they are temperature-stable and sustainable (no additional element needed) [2]. I will highlight examples on electrical conductivity in TiO2 [3], interaction with domain walls in BaTiO3 [1] and photoconductivity [3]. Being arguably the most obvious and appealing, I will outline the various options of dislocation catalysis for sustainability.
We developed black light sintering, because we were searching for a process to insert dislocations during sintering. To heat very fast, we used photon energies above the band gap and can now sinter materials in few seconds without electrical contact and without container. While we failed to insert dislocations, the energy savings as compared to standard heating in furnaces are drastic [4]. The process has been demonstrated on several materials and funding was obtained by SPRIND and ESA. Two of my former PhD students have formed a company with several industry contacts and one of my group leaders covers the fundamental aspects.