Topic: Advanced Polymer-Derived (Ultra)-High-Temperature Resistant Ceramic Nanocomposites for Energy Conversion and Storage

Speaker: Prof. Ralf Riedel

                Technische Universitt Darmstadt, Darmstadt, Germany

Time: 9:00-10:30, (Wed.) Aug. 21, 2019

Venue: Room 468, Lee Hsun Building, IMR CAS

Prof. Riedel got a PhD degree in Inorganic Chemistry in 1986 at the University of Stuttgart. After a PostDoc period at the Max-Planck Institute for Metals Research in Stuttgart, he became Full Professor at the Institute of Materials Science at the Technical University of Darmstadt in 1993. He is an elected member of the World Academy of Ceramics, Fellow of the American Ceramic Society, the European Ceramic Society as well as Fellow of the School of Engineering at The University of Tokyo in Japan. Prof. Riedel was awarded with the Gold Medal for Merits in Natural Sciences and with an honorary doctorate of the Slovak Academy of Science as well as with the Gustav Tammann Prize of the German Society of Materials Science (DGM). In 2009, he received an honorary Professorship at the Tianjin University in Tianjin, China. He is Guest Professor at the Jiangsu University in Zhenjiang and at the Xiamen University in China. Presently, Prof. Riedel holds an Adjunct Professorship at the Northwestern Polytechnical University in Xi′an and is Guest Professor at the University of Tokyo in the group of Prof. Ikuhara, Japan. He is Editor in Chief of the Journal of The American Ceramic Society and of Ceramics International.

Abstract:

Despite significant efforts, which have been made in the last decade(s) in order to reduce the consumption of fossil resources and to move towards low or no emission energy techniques, combustion engines/machines will still play a major role in the next decades. This is partly due to the expected development of the world energy system until the year 2050. Thus, the total world energy consumption is expected to increase from 10 Gto (giga tons of oil equivalent) per year today to 22 Gto per year in 2050, of which fossil fuels (i.e., coal, oil and natural gas) will provide 70% and non-fossil sources (renewable and nuclear energy) 30%. Within this context and considering the limited availability of fossil resources, the development of strategies to increase the efficiency of combustion engines seems to be a logical consequence. As this correlates largely with the firing temperature, serious efforts in developing novel materials with ultrahigh-temperature (UHT) capability have been done recently.

In this presentation, polymer-derived ceramics capable to be operated at ultrahigh temperatures (i.e., T between 1200 and 1400°C) as well as their potential for the fabrication of thermal barrier coatings (TBCs) and environmental barrier coatings (EBCs) will be presented. Beside details on their preparation, physical and thermomechanical properties thereof will be presented. Furthermore, the synthesis and the (U)HT behavior of Si Hf C X-based (X = O, N, B) ceramic nanocomposites will be discussed as novel candidate materials for top coats used in TBC applications in comparison to the zirconia-based state of the art coatings [1]. Information on the processing of the material classes to produce TBC/EBC systems will be also provided. Furthermore, novel candidate substrate materials based on the Mo-Si-B (molybdenum silicide boride) intermetallic system will be introduced, which exhibit improved (U)HT behavior with respect to the state-of-the-art Ni-base superalloys [2].

A second focus will address the application of polymer-derived ceramics for energy storage devices in form of novel anode materials for Li-ion batteries [3]. In particular, the electrochemical behavior of SiOC- and SiCN-based ceramics and composites are discussed.

Reference

1.E. Ionescu, S. Bernard, R. Lucas, P. Kroll, S. Ushakov, A. Navrotsky, and R. Riedel, Polymer-Derived Ultra-High Temperature Ceramics (UHTCs) and Related Materials, Adv. Eng. Mater. 2019, 1900269.

2.E. Ionescu, H.-J. Kleebe, R. Riedel, “Silicon-containing polymer-derived ceramic nanocomposites (PDC-NCs): preparative approaches and properties”, Chem. Soc. Rev. 2012, 41, 5032.

3.M. Heilmaier, M. Krüger, H. Saage, et al., “Current development status of metallic materials for structural applications beyond nickel-base superalloys” JOM 2009, 61, 61.

4.L. M. Reinold, M. Graczyk-Zajac, Y. Gao, G. Mera, R. Riedel, “Carbon-rich SiCN ceramics as high capacity/high stability anode material for lithium-ion batteries”, Journal of Power Sources 2013, 236, 224.