  Sorption and the subsequent desorption of 4He, H2,Ne, N2, CH4 and Kr gas
impurities by graphene oxide (GO), glucose-reduced GO (RGO-Gl) and
hydrazine-reduced GO (RGO-Hz) powders have been investigated in the temperature
interval 2-290 K. It has been found that the sorptive capacity of the reduced
sample RGO-Hz is three to six times higher than that of GO. The reduction of GO
with glucose has only a slight effect on its sorptive properties. The
temperature dependences of the diffusion coefficients of the GO, RGO-Gl and
RGO-Hz samples have been obtained using the measured characteristic times of
sorption. It is assumed that the temperature dependences of the diffusion
coefficients are determined by the competition of the thermally activated and
tunneling mechanisms, the tunneling contribution being dominant at low
temperatures.
