Preparation and characterization of metal oxide CNT-nanoceramic composites

M. Paalo, T. Tätte, M. Hussainov, K. Hanschmidt, M. Lobjakas, A. Lõhmus, U. Mäeorg, I. Kink
University of Tartu, EE

Keywords: nanoceramic, carbon nanotubes, sol-gel

Summary:

During the past decade, significant efforts have been made to transfer carbon nanotubes (CNT) into bulk materials in order to achieve novel functionalities. Ceramic materials community have realized CNTs potential as reinforcement element in the content of brittle ceramic matrices to form novel engineered ceramic matrix composites (CMCs) with superior mechanical, thermal and electrical performance. Among the methods sol-gel method provides an attractive alternative to generate homogeneous CNT-nanoceramic composites. We have previously shown that sol-gel processing enables to achieve metal oxide nanocrystalline materials in various shapes (films, fibers, tubes, microrolls, needles, bulk, as structured surfaces and ect.) at low cost. When reinforced with CNTs, these CMCs structures could be considerable interest for biomedical, optoelectronical and nanotechnological applications. In the current study we describe the preparation and characterization of CMCs fiber structures by using CNT doped titanium alkoxide sols as precursors. CNTs influence on precursor material viscosity parameters was investigated using extensional rheology. CNTs dispersion and alignment inside material, solidified CNT- where investigated by using SEM and FIB. Electrical properties of the materials were measured by 4-point method. The procedure is applicable to obtain CNT-reinforced TiO2, ZrO2, SnO2 and HfO2 materials.