The effect of hydrogen on the morphology of n-type silicon electrodes under electrochemical conditions

We study the electrochemical roughening of a silicon electrode surface during the hydrogen evolution reaction in a fluoride electrolyte using neutron reflection. We demonstrate that as the roughening process modifies the morphology of the silicon surface we can follow the changes by observing the changes in the shape of the total reflection feature.

We assume that the change in the morphology of the surface is due to the diffusion of hydrogen in the silicon electrode. This assumption allow us to model the changes in the reflected intensity at two different angles and find the diffusion exponent for the diffusion of hydrogen in the silicon lattice.