Structure, electrical resistivity, and thermal conductivity of beech wood biocarbon produced at carbonization temperatures below 1000°C

• Published in: Physics of the solid state Vol. 53; no. 11; pp. 2398 - 2407
• Main Authors: Parfen’eva, L. S., Orlova, T. S., Kartenko, N. F., Smirnov, B. I., Smirnov, I. A., Misiorek, H., Jezowski, A., Muha, J., Vera, M. C.
• Format: Journal Article
• Language: English
• Published: Dordrecht SP MAIK Nauka/Interperiodica 01.11.2011; Springer
• Subjects: Diffraction; Electrical conductivity; Nanotechnology; Physics; Physics and Astronomy; Porosity; Pyrolysis; Solid State Physics; Thermal Properties; Toy industry; X-rays; Carb; Tree Wood; Electrical Resistivity; Thermal Conductivity; Amorphous Carbon
• ISSN: 1063-7834; 1090-6460
• DOI: 10.1134/S1063783411110230

This paper reports on measurements of the thermal conductivity κ and the electrical resistivity ρ in the temperature range 5–300 K, and, at 300 K, on X-ray diffraction studies of high-porosity (with a channel pore volume fraction of ∼47 vol %) of the beech wood biocarbon prepared by pyrolysis (carbonization) of tree wood in an argon flow at the carbonization temperature T carb = 800°C. It has been shown that the biocarbon template of the samples studied represents essentially a nanocomposite made up of amorphous carbon and nanocrystallites—“graphite fragments” and graphene layers. The sizes of the nanocrystallites forming these nanocomposites have been determined. The dependences ρ( T ) and κ( T ) have been measured for the samples cut along and perpendicular to the tree growth direction, thus permitting determination of the magnitude of the anisotropy of these parameters. The dependences ρ( T ) and κ( T ), which have been obtained for beech biocarbon samples prepared at T carb = 800°C, are compared with the data amassed by us earlier for samples fabricated at T carb = 1000 and 2400°C. The magnitude and temperature dependence of the phonon thermal conductivity of the nanocomposite making up the beech biocarbon template at T carb = 800°C have been found.