New morphology of a silver chloride surface grown on silver wires

Abstract

Here in, we present an experimental investigation using a very simple and low cost technique to provide new properties of AgCl classical materials at the nanometer scale. Indeed, nano-devices, like nano-sensors for example, require miniaturized reference electrodes with high stability. Miniaturization of the reference electrode has a detrimental effect on its desired characteristics, namely on the potential and lifetime. In this work, the Silver chloride wire, also known as a reference electrode, have been produced using the AC mode by electroplating. We analyze the properties of the surface of the wire by changing the applied potential while the other parameters of electrodeposition are kept the same. Then the morphology of the surface is explored at the microscopic scale with SEM. We found that when the potential applied is under 1 V, the morphology of the surface is a globular one, but this surface is also covered by AgCl crystals which grow in spiral fashion from a screw dislocation. This means that the surface is not completely relaxed even if the electric stability of the wire has been shown. If the potential is increased up to 1 V, the surface is covered by nanosheets. Thus, the surface is entirely relaxed and produces a more stable potential. In addition to increased stability of the wire, nanosheets allow to obtain two-dimensional surfaces which could be increased while the thickness still unchanged.