High-performance polyvinylpyrrolidone capped copper coatings via ultrasonic-assisted supercritical-CO2 electrodeposition: Electrochemical evaluation

The effect of electrodeposition conditions and their influence in electrochemical performance of copper/poly-vinylpyrrolidone (Cu/PVP) composite were investigated and reported here. Initially, the electrochemical performance of the pure Cu coating and the fabricated Cu/PVP composites prepared under conventional method was scrutinized, and the results reveal the enhanced performance of Cu/PVP composite coating when compared to the pure Cu coatings. To improve the deposition quality of Cu/PVP composite coatings, we have utilized two different electrodeposition conditions such as supercritical-CO2 (SC-CO2) and ultrasonic-assisted supercritical-CO2 (US-SC-CO2) conditions. Then the samples were characterized using field emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD), Vickers' hardness test, charge transfer resistance analysis, and corrosion analysis. The corrosion behavior was analyzed through impedance and potentiodynamic polarization techniques in 3.5 wt% NaCl solution. Further, the interfacial charge transfer resistance was examined using the impedance technique in [Fe(CN)(6)](-3/-4) redox probe. The result shows that the electrodeposition quality and performance are enhanced with US-SC-CO2 condition. The introduction of ultrasonic agitation to the SC-CO2 condition, the electrolyte flow rate is enhanced, and fine morphological features are obtained due to the cavitation phenomenon. Thus, the US-SC-CO2 electrodeposition process to Cu/PVP composite coatings enriches overall performance compared to that of SC-CO2 and conventional methods.

Automated summary

The study investigated the influence of electrodeposition conditions on the electrochemical performance of Cu/PVP composite materials, with results indicating that the electrodeposition quality and performance were optimal under ultrasonic-assisted supercritical-CO2 (US-SC-CO2) conditions.