A comparative study of the porosity of doped graphites by small angle neutron scattering, nitrogen adsorption and helium pycnometry

The porosity of undoped and Zr- and Ti-doped graphites has been determined using ultra small and small angle neutron scattering, nitrogen adsorption and helium pycnometry. To differentiate between open and closed in the neutron measurements the contrast matching technique was employed. It is shown that the combination of the three techniques is necessary for an accurate determination of the porosity and for the assessment of the structural modifications arising from the doping which results in the transformation of open porosity to closed.