Electrosynthesis of Intrinsically Conducting Polymers/Silicon Nanocomposites: Formation Mechanism and Optical Properties

F.A. Harraz, A.M. Salem
Central Metallurgical R&D Institute (CMRDI), EG

Keywords: porous silicon, conducting polymers, electrochemical technique, optical properties


When a silicon wafer is subjected to electrochemical etching in fluoride-based solution, silicon surface develops pores, often called porous silicon (PSi). A variety of pore sizes ranging from a few nanometers up to a few micrometers can be obtained during the etching process. In this study, we extended our previous works to electro-polymerize various conducting polymers, including polypyrrole (PPy), polyaniline (PA) and polythiophene (PT) into PSi templates. MEH-PPV polymer was also tested for filling the PSi matrix using the spin coating technique. The main objective of this study is to fill completely the PSi with conducting polymers with an ultimate goal to fabricate a novel nanocomposite with improved electrical and optical properties. Another objective is to understand the distribution and filling mechanism of polymer inside the nanopores. Our findings revealed that the deposition of polymer proceeds homogeneously inside the nanopores, starting from the pore bottom and propagates into the outer surface. Electrical and optical properties of as-synthesized nanocomposites were significantly enhanced. Such hybrid nanostructures could be beneficial to current and future technologies based on conducting polymers, including for example, photovoltaic device and sensing applications. Results of fabrication and characterization will be addressed and thoroughly discussed during the conference.