Research on environmentally friendly energy storage devices is a necessary solution to solve the energy crisis and environmental pollution caused by it. A major challenge for superbarriers is to introduce cost-effective, stable and suitable electrode nanomaterials for further industrialization of these tools. For this purpose, in this research, a polyaniline electrode using a nickel foam substrate for use in supercapacitors was made. Using X-ray diffraction analysis, the crystal structure was studied and its surface morphology was examined using a scanning electron microscope. In addition, Idex mapping analysis showed the elements on the surface and how they are distributed. Investigations of current-voltage cycles were performed at different scanning speeds. The fabricated electrode showed faradaic behaviour with electron transfer. In addition, the electrochemical resistance was investigated using electrochemical impedance analysis, and the resistance due to charge transfer was found to be approximately 1.2 ohms. Finally, electrochemical investigations showed a specific capacity of 1100 F/g at a current density of 1 A/g.

In this paper, the behavior of the salicylate anion-selective electrode was studied using the electrochemical impedance spectroscopy technique. Considering the diagram of the charge transfer resistance and -logarithm of the double layer capacitance versus -logarithm of the concentration, linear range concentration increased to 1.0×10-8-1.0×10-1 M and 1.0×10-9-1.0×10-1 M, respectively. Among the other characteristics of this study, it can be pointed out a wide pH range of 4.0-10.0. Then ‘one-impedance for one-concentration’ method was used to measure the salicylate ion at the linear range of 1.0×10-8-1.0×10-1 M. Finally, the impedance spectra of this electrode were simulated in which the obtained results of this simulation indicate proximity of experimental and simulation data.

Photovoltaic systems, for example, dye-sensitized solar cells (DSSCs), are one of the useful tools for producing renewable and green energy. To develop DSSCs technology, it is necessary to overcome obstacles such as the need for expensive compounds. Organic dyes system containing responsible group for using in dye-sensitized solar cells and effective anchoring group for improving interaction between dye (photosensitizers) and nanolayer were designed and prepared. A series of DSSCs were designed and manufactured based on organic dyes as photosensitizers. The π-electrons in the HOMO orbitals of the dyes are delocalized only in dyes 1 and 2. A new MoS2/GO hybrid or composite was also employed instead of platinum. The DSSCs were prepared using MoS2/GO hybrid or composite and compared with that containing platinum. Under same conditions, the DSSCs with MoS2/GO composite illustrated better efficiency than MoS2/GO hybrid. The proposed dyes used as photosensitizer in a dye solar cell structure in the presence of Na-doped TiO2 and their photovoltaic properties investigated. The highest PCE in the presence of GO/MoS2 nanocomposite as opposite electrode and TiO2 and Na-doped TiO2 is 5.14 and 5.48, respectively, and corresponds to dye 8. The improved performance of Na doped TiO2 based DSSC could be attributed to the enhancement in optical properties of the sample by decreasing the intrinsic defects.

In this work, nanolayered Ti3C2 was applied to construct a modified screen printed electrode (SPE). This modified electrode (Ti3C2/SPE) was applied for detecting tyrosine with various voltammetric procedures. Modifying the working electrode increased electro-oxidation of tyrosine as the current intensity enhanced. Moreover, Ti3C2/SPE was employed for determining tyrosine in concentration ranges from 0.5-700.0 μM with the low LOD of 0.15 μM using DPV.

In this study, cytosine (CT) modified glassy carbon (GC) electrode was used to investigate the detectability of caffeine (CAF) found in foods such as tea, coffee and soft drinks. Using the cyclic voltammetry (CV) technique, 1 mM CT was prepared in pH 7.2 phosphate buffer solution (PBS) and modified at a scanning rate of 100 mV s-¹ in the potential range of 1.0 V to 2.1 V. CT/GC electrode was characterized by CV, scanning electron microscope (SEM) and electrochemical impedance spectroscopy (EIS) techniques. 1 mM CAF solutions were prepared in different supporting electrolytes such as H₂SO₄, HCl, HNO₃, and CH₃COOH within the potential range of +0.5 V to +1.7 V using square wave voltammetry (SWV) technique. Effect of the supporting electrolyte concentrations were investigated. CAF solutions in the concentration ranges of 0.75 to 0.05 mM and 0.025 to 0.0025 mM were prepared in 100 mM H₂SO₄ supporting electrolyte and calibration graphs were drawn. Line equations were created using the values ​​read from the drawn graphs. Correlation coefficient (R2) values ​​were calculated as 0.9947 and 0.9961, respectively. Using the calibration curves, limit of detection (LOD) and limit of quantification (LOQ) were found as 0.93 µM and 2.79 µM.

This work intends to study the possible effect of reference electrode impedance on the working electrode impedance. For this purpose, various electrode/electrolyte systems were examined by electrochemical impedance spectroscopy (EIS) using reference electrodes having different impedance. In the experiments, working electrode impedance were around 1 and 10 kohm. cm2; and the reference electrode impedance were in the range of 1-10 kohm. The results showed that utilizing reference electrode with highest impedance resulted in distortion from actual impedance spectra in high or low frequency region which is of particular importance for corrosion inhibition studies.