Implications of the Electrodeposition Scan Rate on the Morphology of Polyaniline Layer and the Impedance of a QCM Sensor

Abstract

This work aims to determine how the scan rate affects PANI layers' morphology and resonance parameters deposited on quartz crystal microbalance (QCM). The PANI layer was produced using the electrodeposition method with a scan rate variation of 10 to 50 mV/s. The PANI layer deposited at a scan rate of 10 mV/s has an aggregate morphology, whereas the morphology becomes more scattered at a higher scan rate. On the other hand, the homogeneity of the distribution of PANI particles increases due to the increase in the scan rate. The QCM impedance profile also changes with PANI layer deposition at different scan rates. The QCM impedance profile with the PANI layer that is most similar to the uncoated QCM impedance profile is at a scan rate of 10, 40 and 50 mV/s. The resonance parameters, which represent the inertial mass and the dissipative characteristics of the PANI layer, were investigated. The PANI layer with the smallest resonance parameter has a scan rate of 10 and 40 mV/s. Therefore, the 2 scan rates are the best candidates to be applied further. HIGHLIGHTS The electrodeposition scan rate influences the morphology of the PANI layer deposited above QCM The amount of carbon distributed across the QCM surface represents how effective the PANI deposition was The resulting morphology will impact the PANI layer's impedance characteristic and resonance parameter values GRAPHICAL ABSTRACT

Electrodeposition of Polyaniline on Tantalum: Redox Behavior, Morphology and Capacitive Properties

“…An increase in the PANI oxidation current Current densities assigned to the redox behavior of the electrodeposited PANI become higher by decreasing υ during the polymerization stage within both regions, namely −1.2-1.5 V SCE (Figure 5c) and −1.2-0.8 V SCE (Figure 5d). An increase in the PANI oxidation current observed by decreasing the synthesis potential scan rate was also observed for other substrates, such as AISI 304 stainless steel [17], Ti [22], Pt [34], Ni [35] and Ag [36]. Using υ in the range of 10 and 100 mV s −1 for the ANI polymerization on Pt shows that the peak current density j p linearly decreases due to PANI oxidation, with υ 1/2 indicating a masstransport control [34].…”

“…observed by decreasing the synthesis potential scan rate was also observed for other substrates, such as AISI 304 stainless steel [17], Ti [22], Pt [34], Ni [35] and Ag [36]. Using υ in the range of 10 and 100 mV s −1 for the ANI polymerization on Pt shows that the peak current density jp linearly decreases due to PANI oxidation, with υ 1/2 indicating a mass-transport control [34].…”

“…Several parameters, such as the electrode substrate, the potential scan rate and the potential window, as well as the sulfuric acid and ANI concentrations from which the PANI synthesis was carried out using cyclic voltammetry, were found to affect the mor-phology, along with other properties of the deposited PANI [2,17,[35][36][37][38][39][40]. Examples of SEM images taken for the Ta 2 O 5 -PANI|PANI films deposited on Ta using cyclic voltammetry at υ = 20, 50 and 100 mV s −1 from 1.0 M H 2 SO 4 solution containing 0.2 M ANI are illustrated in Figure 8.…”

Synthesis and Characterization of PVA/PANI Nanofiber as Active Material for Humidity Sensors

“…The Peaks present at specific wavenumbers will indicate the types of functional groups or bonds in a material. The wavenumber values obtained are compared with reference functional groups from previous research [20]. The FTIR characterization was conducted on PVA and PVA/PANI nanofiber samples.…”