Fabrication of electroactive multi-layered polyazulene thin films by atmospheric pressure-vapor phase polymerization

Abstract

<p><br></p><p><a href="https://www.sciencedirect.com/topics/materials-science/thin-films" title="Learn more about Thin films from ScienceDirect's AI-generated Topic Pages">Thin films</a> of polyazulene (PAz) are produced by using an optimized atmospheric pressure–vapor phase <a href="https://www.sciencedirect.com/topics/physics-and-astronomy/polymerisation" title="Learn more about polymerization from ScienceDirect's AI-generated Topic Pages">polymerization</a> (AP-VPP) method. Method optimization is carried out by studying the effect of cell temperature, substrate temperature, polymerization time, and washing-solvent on film properties like optical bandgap, sheet resistance, <a href="https://www.sciencedirect.com/topics/physics-and-astronomy/surface-roughness" title="Learn more about surface roughness from ScienceDirect's AI-generated Topic Pages">surface roughness</a>, and % <a href="https://www.sciencedirect.com/topics/physics-and-astronomy/transmittance" title="Learn more about transmittance from ScienceDirect's AI-generated Topic Pages">transmittance</a> (%T). Multi-layered PAz films were produced by layer-by-layer engineering. The effects of thin, electroactive multiple layers on film properties are investigated. UV–Vis, IR, and Raman analysis are utilized to understand the extended conjugation length and nature of the charge carriers. The spectroscopic data revealed the anomalous behaviour of PAz at a high level of doping. The proportion and amount of quinoid conformation is discussed. The addition of layers changes the transport of ions across the electroactive PAz films, which is studied using <a href="https://www.sciencedirect.com/topics/materials-science/cyclic-voltammetry" title="Learn more about cyclic voltammetry from ScienceDirect's AI-generated Topic Pages">cyclic voltammetry</a> at various scan rates. AFM and SEM images reveal a change in structural properties which is further correlated with a deviation of capacitance values at elevated scan rate. Comparison with earlier reported literature on electrochemically and chemically synthesized PAz is also provided. The <a href="https://www.sciencedirect.com/topics/materials-science/conductivity" title="Learn more about conductivity from ScienceDirect's AI-generated Topic Pages">conductivity</a>, transparency and high capacitance show a promising application of AP-VPP PAz in various fields.<br></p>