Enhancing the electrochemical properties of the p-type conductive polymer on the surface of the new synthesized 2-(pyridin-3-ylmethylene) hydrazine-1-carbothioamide-modified electrode: computational and electrochemical study

Abstract

Herein, 2-(pyridin-3-ylmethylene)hydrazine-1-carbothioamide(3PHCT)was first fabricated through a chemical method, and subsequently, polyorthoaminophenol (POAP)/3PHCT films were prepared using electropolymerization of POAP, carried out in the presence of the as-prepared 3PHCT to serve as the active electrode for electrochemical application. Geometry optimization and calculations of structural and electronic/vibrational properties of the 3PHCT system are studied (based on the quantum atom-in-molecule theory, QTAIM). In addition, the local intra-molecular electron density, and its Laplacian, and, thus, intra-molecular virial forces, of this molecule system are calculated. These results show that the oxygen and sulfur atoms play domain role in intra-molecular charge and energy transfer in this molecular system. In addition, based on the QTAIM, it is predicted that a single electrochemical molecular system can be grouped into p-type-like and n-type-like sections, and would be good candidate to reduce intra-molecular repulsion of the bipolaron during electrochemical polymerization of POAP. Galvanostatic charge–discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy, were conducted to characterize the prepared composite films and investigate the performance of the system, respectively. In this study, novel POAP/3PHCT are presented for electrochemical redox capacitors possessing the merits of high active surface area, stability in an aqueous electrolyte and ease of synthesis.