BioResources (Jul 2016)
Synthesis of Biomorphic Charcoal/TiO2 Composites from Moso Bamboo Templates for Absorbing Microwave
Abstract
Biomorphic charcoal/TiO2 composites (C/TiO2) from moso bamboo templates were produced for absorbing microwave. Subsequently, the characteristics of the C/TiO2 were investigated by scanning electron microscopy, thermogravimetric analysis, and vector network analysis. The results showed that the biomorphic microstructure of the moso bamboo charcoal was duplicated in the C/TiO2. Thus, the density of the C/TiO2 sintered at 1200 °C was lower and approximately 0.916 ± 0.003 g/cm3. Moreover, the ignition, the maximum combustion, and the burnout temperatures of the C/TiO2 sintered at 600 °C were ~320 °C, ~530 °C, and ~585 °C, respectively. Additionally, with the rising of the temperature sintering C/TiO2, the microwave absorbency of the C/TiO2 was improved over high frequency zones. Furthermore, the average imaginary-part values of the permittivity of the C/TiO2 sintered at 600 °C and 1200 °C notably increased by 11.16-fold. In addition, the peak of microwave reflection loss of the samples (2.0 mm thickness) from the C/TiO2 powder (wt. 20%) sintered at 1200 °C and the paraffin wax (wt. 80%) was observed as -18.0 dB at 17.4 GHz. Therefore, the C/TiO2 sintered at higher temperatures exhibited lower geometrical density, better thermostability, and favorable microwave absorptive properties.
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