On the voltage-controlled assembly of nanoparticle arrays at electrochemical solid/liquid interfaces

Research in the field of nanoplasmonic metamaterials is moving towards more and more interesting and, potentially useful, applications. In this paper we focus on a class of such metamaterials formed by voltage controlled self-assembly of metallic nanoparticale at electrochemical solid |liquid interfaces. We perform a simplified, comprehensive analysis of the stability of a nanoparticle arrays under different conditions and assembly. From the Poisson-Boltzmann model of electrostatic interactions between a metallic nanoparticle and the electrode and between the nanoparticles at the electrode, as well as the Hamaker-Lifshitz theory of the corresponding van der Waals interactions, we reach some conclusions regarding the possibility to build arrays of charged nanoparticles on electrodes and disassemble them, subject to variation of applied voltage. Since systems of this type have been shown, recently, to provide nontrivial electrotuneable optical response, such analysis is crucial for answering the question whether the scenarios of electrochemical plasmonics are feasible.