I need to estimate the interaction energy of a hydroxide ion with a palladium surface of $-0.6$V in water.
I know that the electric field of a charge $e$ is $$ E = \frac{1}{4\pi\epsilon}\frac{e}{r^2} $$
where $r$ is the distance and $\epsilon$ is the dielectric constant.
Also, I know that for an infinity charged plane the electric field is $$ E=\frac{\sigma}{2\epsilon} $$
where $\sigma$ is the surface charge density. I have the area of the surface, $A=0.125$ cm$^2$. But I wonder how can I calculate this interaction energy.
