Following the intercalation process of H2SO4 into pyrographite by x-ray microscopy

A time series of radiographic images with a lateral resolution in the micrometer range has been recorded in order to follow, in situ, the intercalation process of H2SO4 into pyrographite. The use of x-ray microscopy allows us to visualize and to quantify intercalation fronts inside the specimen giving direct access to intercalation velocities and hence to mobility and diffusion coefficients. The coexistence of various fronts is demonstrated in metastable kinetics situations.