Site‐Selective Bipolar Electrodeposition of Gold Clusters on Graphene Oxide Microsheets at a 3D Air|Liquid Interface

Abstract An innovative wireless approach is proposed for asymmetric site‐selective deposition of gold clusters on graphene oxide microsheets by performing bipolar electrochemistry at the 3D air|liquid interface present in an assembly of bubbles constituting a foam. Exfoliated graphene oxide (EGO) microsheets are introduced into a bipolar electrochemical cell, which is filled with the foam composed of a nonionic surfactant, water, and a gold metal precursor. The EGO microparticles are located exclusively at the air|liquid interface, providing a unique 2D reaction space for bipolar electrodeposition, deployed in the 3D volume of the reactor. The application of an external electric field on such a medium enables a focalization of the polarization potential gradient and simultaneously restricts the mobility of the EGO particles, leading to their preferential in‐plane orientation with respect to the electric field lines, greatly facilitating their successful site selective modification with gold clusters.