Electrochemical measurements of the electronic density of states

We present a simple electrochemical method, called intercalation spectroscopy, to study the electronic density-of-states of intercalation materials. It is based on the realization that electrochemical quasi-steady state potential curves of a number of materials exhibit fine structure in good agreement with features in the density of electronic states. Different electrochemical techniques are able to give this information, but chronopotentiometry appears to have advantages from an experimental viewpoint. In this paper we compare the so called 'electrochemical density-of-states' of amorphous and crystalline structures. We also address the limitations of intercalation spectroscopy due to kinetic effects, i.e. very slow relaxations of the charge carriers. Intercalation spectroscopy is in principle very sensitive, although in limited energy ranges, and is able to give information complementary to electron and x-ray spectroscopies for a number of materials.