Effect of carbonization temperature on crystalline structure and properties of isotropic pitch-based carbon fiber

Abstract

Isotropic pitch-based fibers produced from coal tar pitch with the melt-blowing method were carbonized at temperatures ranging from 800 to 1600 o C to investigate their crystalline structure and physical properties as a function of the carbonization temperature. The in-plane crystallite size (L a ) of the carbonized pitch fiber from X-ray diffraction increased monotonously by increasing the carbonization temperature resulting in a gradual increase in the electrical conductivity from 169 to 3800 S/cm. However, the variation in the d 002 spacing and stacking height of the crystallite (L c ) showed that the structural order perpendicular to the graphene planes got worse in carbonization temperatures from 800 to 1200 o C probably due to randomization through the process of gas evolution; however, structural ordering eventually occurred at around 1400 o C. For the carbonized pitch powder without stabilization, structural ordering perpendicular to the graphene planes occurred at around 800-900 o C indicating that oxygen was inserted during the stabilization process. Additionally, the shear stress that occurred during the melt-blowing process might interfere with the crystallization of the CPF.

Temperature and Copper Concentration Effects on the Formation of Graphene-Encapsulated Copper Nanoparticles from Kraft Lignin

“…Peaks could be located around 1600 cm −1 and 1000 cm −1 for Cu-lignin samples, which indicated that graphene layers were detected. Both samples with lignin only and Cu-lignin mixture samples heated at 600 °C had significantly higher carbonization yields than 800 °C, followed by 1000 °C, which had the same trend as reported by Kim’s group [22]. …”

Stabilisation of sheep wool fibres under air atmosphere: Study of physicochemical changes

“…The broadness of G band also confirmed this observation, with full width at half-maximum values (ca. 89-97) comparable to those reported for stabilised pitch fibres [34]; the values for D band are higher due to a large contribution of defects. SEM (Figure 8) explored the morphology of the fibres upon stabilisation.…”

Activation of electrospun carbon fibers: the effect of fiber diameter on CO2 and steam reaction kinetics

“…The y-axis intercept is significantly lower than unity in both cases with (84.0 ± 1.2)% and (82.77 ± 0.47)%. A plausible explanation for the specific conductance reductions at zero burn-off are chemical or changes of the crystalline structure [67] at the early stages of the activation process. Considering the delay of burn-off and specific ECAS development discussed in Section 3, it seems more likely, that the formation of oxygen-containing functionalities is responsible for the apparent conductance changes at zero-burn-off.…”