Synthesis and electrochemical investigation of cluster assembled carbon thin films

Nanostructured materials grown by the deposition of clusters with low kinetic energy are unique systems that preserve the original size dependent features of their building blocks. As porous materials with high surface to volume ratio they have a tremendous technological potential toward the development of green, cheap and efficient energy storage and harvesting systems, including carbon based supercapacitors. This thesis is devoted to the synthesis and electrochemical investigation of nanostructured carbon (ns-C) thin films and composites grown by the Supersonic Cluster Beam Deposition (SCBD) of clusters formed in a Pulsed Microplasma Cluster Source (PMCS). The electrochemical properties of cluster assembled thin films are assessed by the study of the electric double layer (EDL) formed at the interface between ns-C based electrodes and a liquid electrolyte. Ns-C behavior as electrode material has been characterized as function of thickness, post deposition thermal treatment, metal nanoparticles embedding and electrolyte type. This study is carried out by means of atomic force microscopy (AFM), Raman spectroscopy, x-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and electrochemical techniques, such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Our results establish the feasibility of the SCBD technique for the synthesis of nanostructured carbon and metal:carbon nanocomposite thin films with promising potential as porous material for thin film electrochemical energy storage.