Phase Transitions in Graphite Oxide Solvates at Temperatures Near Ambient.
It is demonstrated that solvent-saturated graphite oxide can be considered to be solid solvate, and two phases with distinctly different solvent composition are found near room temperature. Phase transitions between these two solvated phases were observed using synchrotron powder X-ray diffraction and DSC for methanol, ethanol, acetone, and dimethylformamide (DMF) solvents. Solvate A, formed at room temperature, undergoes a reversible phase transition into expanded Solvate L at temperatures slightly below ambient due to insertion of one monolayer of solvent molecules between the GO planes. The phase transition is reversible upon heating, whereas the low-temperature expanded phase L can be quenched to room temperature for ethanol and DMF solvates.
Department of Physics, Umeå University, SE-901 87 Umeå, Sweden.
Shujie
S
You
Department of Physics, Umeå University, SE-901 87 Umeå, Sweden.
Serhiy
S
Luzan
Department of Physics, Umeå University, SE-901 87 Umeå, Sweden.
Junchun
J
Yu
Department of Physics, Umeå University, SE-901 87 Umeå, Sweden.
Bertil
B
Sundqvist
Department of Physics, Umeå University, SE-901 87 Umeå, Sweden.
Alexandr V
AV
Talyzin
graphene; graphite oxide; phase transitions; solvates