Abstract

The carbonization of bamboo at 400 °C–700 °C resulted in the formation of graphite crystals embedded in amorphous carbon. The high dielectric constants (≈10³ at 1 Hz) of these carbon materials were attributed to the presence of polar groups such as -OH, -NH₂ and -COOH with marginal contribution from interfacial polarization. The dielectric constants were observed to be frequency-dependent and found to be decreased with increasing frequency. The measured dielectric loss was also found to be decreasing with increasing frequency. Conductance dominant dielectric loss observed in 400 °C–600 °C annealed samples was further supported by the Cole-Cole plot. Maxwell–Wagner–Sillars interfacial polarization relaxation along with conduction loss was observed only for the 700 °C annealed sample.

摘要

竹子在 400°C–700°C 的碳化导致形成嵌入无定形碳中的石墨晶体。这些碳材料的高介电常数（≈10 ³ at 1 Hz）归因于极性基团如-OH、-NH ₂和-COOH 的存在，界面极化的贡献很小。观察到介电常数与频率有关，并且发现随着频率的增加而降低。还发现测量的介电损耗随着频率的增加而降低。Cole-Cole 图进一步支持了在 400 °C–600 °C 退火样品中观察到的电导主导介电损耗。仅在 700 °C 退火样品中观察到 Maxwell-Wagner-Sillars 界面极化弛豫和传导损耗。