Electronic and Self-healing Properties of Polymer-Inorganic Hybrids Enabled by Vapor Phase Infiltration
- Author
- Oksana Yurkevich
- Year
- 2022
- Abstract & Cover
- Source of Information
- Oksana Yurkevich
- University
- CIC nanoGUNE Nanomaterials group (San Sebastián, Spain)
- External Link
- Read Thesis
Enabling self-healing of materials is crucially important for saving resources and energy in numerous emerging applications. A plethora of recently published research works is dedicated to the development of strategies which allow for self-healing of materials, especially of those with certain technological importance. Given that most of the approaches are based on chemical processes, the vast majority of these works focus on the self-healing of organic materials, specifically polymers. At the same time, there is a growing demand for adapting such functionality to inorganic materials due to their importance in most developed electronics, including flexible electronics. The few existent examples of self-healing of inorganic materials rely on the incorporation of liquid healing agents, such as liquid metals or liquid precursors, into the devices. However, the development is in its infancy and further progress remains very challenging, mainly because of a lack of feasible healing agents and suitable ways to supply them to the damaged site.
In this thesis we have developed a concept for the self-healing of metal oxides, which is the most challenging type of material in this research area. This concept consists of growing metal oxide nanoparticles inside the bulk of halogenated polymers via vapor phase infiltration and their subsequent entropy-driven migration to externally induced defect sites, which eventually leads to the recovery of the defect. The hybrid material, i.e., the polymer matrix with dispersed NPs, can serve as a reservoir with healing agents for the repair of a cracked MeO film. The self-healing of inorganic materials and structures was realized also without liquid agents by making use of the mobility of inorganic NPs within polymers, as the spatial distribution of NPs can be tuned by means of harnessing both enthalpy and entropy.
Herein we present an expansion of the pool of self-healing materials to semiconductors such as indium, zinc, indium tin and zinc indium oxides, thereby allowing to increase the reliability and sustainability of future functional materials. We revealed that not only the morphology, but also the electrical properties of ITO can be largely restored upon healing. Such properties are of immediate interest for the further development of transparent flexible electrodes.