关键词: 三维石墨烯类多孔碳, 煤沥青, 模板, 催化氧还原性能

Abstract:

The 3D graphene type porous carbon was prepared using coal tar pitch as carbon source and nano Fe(OH)₃ as template. Optimal conditions for the catalytic oxygen reduction performance were determined as: the mass ratio of coal tar, nano Fe(OH)₃ and KOH is 6:8:4; the pyrolysis temperature is 800 ^oC. SEM images show that the products have uniformly porous structure. TEM images demonstrate that the products are porous with foam shapes. HRTEM images further indicate that the products have formed several-layers 3D graphene structure, which are also supported by XRD and Raman data, and the pore size mainly distributes in 10 ~ 40 nm. XRD data show that the materials have a certain degree of graphitization. XPS spectra indicate that nano Fe(OH)₃  template is washed out with no iron being detected and C element content is about 88.7% mainly comprising C—C bond. BET results demonstrate that the specific surface area is 2040 m²•g^-1, the pore size distribution concentrates in 10 ~ 40 nm which is consistent with the results obtained by HRTEM. Electrochemical performances were tested in 0.1 mol•L^-1 KOH, the initial reduction potential is 0 V (vs. Hg/HgO ) and the electron transfer number is 3.58. Such low-cost, good performance material is potentially useful for oxygen reduction catalyst.

Key words: 3D graphene type porous carbon, coal tar pitch, template, catalytic oxygen reduction performance