Synthesis of 9‐(4‐nitrophenylsulfonyl)‐9H‐carbazole: Comparison of an impedance study of poly[9‐(4‐nitrophenylsulfonyl)‐9H‐carbazole] on gold and carbon fiber microelectrodes

Abstract

In this study, 9-(4-nitrophenylsulfonyl)-9Hcarbazole (NPhSCz) monomer was chemically synthesized. The monomer characterization was performed by Fourier transform infrared spectroscopy, 1 H-NMR, and melting point analysis. Two different electropolymerizations of NPhSCz were studied on a gold microelectrode (Au electrode) and carbon fiber microelectrodes (CFMEs) in a 0.1M sodium perchlorate (NaClO 4 )/acetonitrile solution. The electropolymerization experiments were done from 1 to 4 mM. The characterizations of two different modified electrodes of poly[9-(4-nitrophenylsulfonyl)-9H-carbazole] [poly(NPhSCz)] were performed by various techniques, including cyclic voltammetry, scanning electron microscopy-energy-dispersive X-ray analysis, and electrochemical impedance spectroscopy (EIS). The effects of the initial monomer concentrations (1, 2, 3, and 4 mM) were examined by EIS. The capacitive behaviors of the modified electrodes were defined via Nyquist, Bode magnitude, Bode phase, and admittance plots. The variation of the low-frequency capacitance (C LF ) and double-layer capacitance (C dl ) values are presented at different initial monomer concentrations. Poly(NPhSCz)/CFME was more capacitive (C LF ¼ 6.66 F/cm 2 and C dl % 28 mF) than the Au electrode (C LF ¼ 6.53 F/cm 2 and C dl %

SnO2Quantum Dots-Reduced Graphene Oxide Composite for Enzyme-Free Ultrasensitive Electrochemical Detection of Urea

“…However, in this case, the value of n was found to be 0.88. As this value lies between 0.5 and 1, the effect may be attributed to surface roughness or due to surface heterogeneity caused by the deposition of urea . Such surface occurs as a result of surface coupling between nonhomogeneous double layer capacitance and the electrolyte resistance.…”

“…As this value lies between 0.5 and 1, the effect may be attributed to surface roughness or due to surface heterogeneity caused by the deposition of urea. 35 Such surface occurs as a result of surface coupling between nonhomogeneous double layer capacitance and the electrolyte resistance. R 1 and R 2 are in the parallel connection in the circuit, and R 2 is the charge transfer resistance of the system.…”

Fabricating binary anti-corrosion structures containing superhydrophobic surfaces and sturdy barrier layers for Al alloys

“…Therefore, the value of impedance modulus at low frequency, semicircle diameter and R ct can be applied as indicators of anti-corrosion property. 42 Based on above reported literature, the schematic shown in Fig. 12 was drawn to intuitively describe the anti-corrosion mechanism of self-assembled anodic oxide lms with regular binary structure.…”