Surface reconstruction of electron injection layers based on conjugated oligoelectrolytes atop an electroluminescent layer occurs in the presence of air. The proposed mechanism involves hydration and concomitant increase of the interfacial energy with the underlying hydrophobic surface followed by dewetting via a nucleation process. No such changes are observed in the case of a conjugated polyelectrolyte, presumably because the lower mobility of the polymer chains leads to a kinetically locked bilayer.