Open AccessEffect of long-term ageing on graphene oxide: structure and thermal decomposition
Author(s) -
Chen Li,
Yanling Lü,
Jun Yan,
Weibo Yu,
Ran Zhao,
Shiguo Du,
N. Ke
Publication year - 2021
Publication title -
royal society open science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.84
H-Index - 51
ISSN - 2054-5703
DOI - 10.1098/rsos.202309
Subject(s) - graphene , ageing , oxide , oxygen , decomposition , thermal decomposition , activation energy , desorption , materials science , chemistry , nanotechnology , adsorption , organic chemistry , metallurgy , biology , genetics
After long-term ageing, the structure of graphene oxide prepared by the modified Hummers method changed. Because of the desorption of oxygen-containing functional groups, the C/O ratio of graphene oxide increased from 1.96 to 2.76. However, the average interlayer distance decreased from 0.660 to 0.567 nm. The content of -CH- and -CH2 - decreased; however, the type of oxygen-containing functional groups did not change. Moreover,I D /I G increased from 0.87 to 0.92, indicating that the defect density decreased because of desorbing oxygen functional groups after ageing. When the temperature exceeded 60°C, CO2 produced by decomposing graphene oxide was detected. The thermal decomposition changed after ageing. The decomposition peak temperature decreased from 216°C to 195°C. The CO2 amount produced remained almost unchanged; however, the amount of CO, SO2 and H2 O decreased. After ageing, the apparent activation energy of graphene oxide decreased from 150 to 134 kJ mol−1 .