Department of Energy Engineering (Energy Engineering)The study of chemical structure is crucial in chemistry and materials science. Materials structure can be classified in various ways, and the most familiar approach is to classify them according to the dimension
of structure. For example, carbon composed of the same elements can be categorized into zero-dimensional
(0D) fullerene, one-dimensional (1D) carbon nanotube, two-dimensional (2D) graphene, and three- dimensional (3D) diamond, but due to particular arrangements of atoms the properties are significantly different depending on the structural dimension. Bearing this in mind, many organic structures were created by designing the symmetry of the molecules and using the polymerization to control the size of the structure (bottom-up strategy). The synthesized organic structures showed applicability to various applications such as gas separation, storage, membrane, and catalysis, etc. depending on the structural dimension. However, covalently bonded organic structures are limited in some areas because they are thermally unstable and have low conductivity. This thesis presents the results of applying a fully-fused aromatic networks (FANs) structure to energy materials to overcome the aforementioned limitations. The fused-ring has no free torsional motion, allowing stable electron transfer and providing thermal and chemical stability. By using these properties, the iron particles were encapsulated in the 2D structure, which showed excellent activity as a semi-permanent oxygen reduction catalyst and the 3D structure exhibited high hydrogen storage with excellent thermal stability. In addition, a new type of 2D structure that introduces insights into how to design materials in organic structures for gas separation and storage. Based on these studies, it is shown that FANs can be a
promising material for electrochemical catalysts, gas storage, separation by using advantage of excellent electron mobility and thermochemical stability. Furthermore, I also studied carbon material as a catalyst having excellent activity and good stability in the conversion of ethylbenzene into styrene.clos
