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Different types of solvents, aromatic and aliphatic, are used in many industrial sectors, and long-term exposure to these solvents can lead to many occupational diseases. Therefore, it is of great importance to detect volatile organic compounds (VOCs) using economic and ergonomic techniques. In this study, two macromolecules based on pillar[5]arene, named P[5]-1and P[5]-2, were synthesized and applied to the detection of six different environmentally volatile pollutants in industry and laboratories. The thin films of the synthesized macrocycles were coated by using the spin coating technique on a suitable substrate under optimum conditions. All compounds and the prepared thin film surfaces were characterized by NMR, Fourier transform infrared (FT-IR), elemental analysis, atomic force microscopy (AFM), scanning electron microscopy (SEM), and contact angle measurements. All vapor sensing measurements were performed via the surface plasmon resonance (SPR) optical technique, and the responses of the P[5]-1and P[5]-2thin-film sensors were calculated with ΔI/Io× 100. The responses of the P[5]-1and P[5]-2thin-film sensors to dichloromethane vapor were determined to be 7.17 and 4.11, respectively, while the responses to chloroform vapor were calculated to be 5.24 and 2.8, respectively. As a result, these thin-film sensors showed a higher response to dichloromethane and chloroform vapors than to other harmful vapors. The SPR kinetic data for vapors validated that a nonlinear autoregressive neural network was performed with exogenous input for the best molecular modeling by using normalized reflected light intensity values. It can be clearly seen from the correlation coefficient values that the nonlinear autoregressive with exogenous input artificial neural network (NARX-ANN) model for dichloromethane converged more successfully to the experimental data compared to other gases. The correlation coefficient values of the dichloromethane modeling results were approximately 0.99 and 0.98 for P[5]-1and P[5]-2thin-film sensors, respectively.

This study demonstrated the electrochemical deposition of Mn-doped ZnO films under hydrothermal conditions at 130degC in 50% v/v DMSO-H2O mixture. X-ray diffraction analysis showed that the deposition of the ZnO structures was along (002) direction. However, the presence of Mn2+ affected the thickness of ZnO structures and we believe that the interaction of Mn2+ with the nonpolar surface of ZnO restricts lateral growth. Mn appears in the mixed oxide state in ZnO lattice. The photoluminescence spectra of the films show only UV emission indicating high crystal quality. The blueshift of the UV emission is observed after the introduction of Mn impurity into the ZnO lattice. The surface morphology, lattice structure, Mn content, chemical binding characteristics, and optical properties of the deposits were examined by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and photoluminescence spectroscopy, respectively.

In this study, electrochemical growth of Ce-doped α-Fe2O3films is reported. Electrodeposition at 75°C and also a combined hydrothermal-electrochemical method to obtain hematite are presented. Both acidic and neutral plating solutions were used for the depositions. Ferric oxyhydroxide is produced by electrodeposition at 75°C and converted to hematite phase after annealing. Hydrothermal-electrodeposition at 130°C results in formation of hematite phase directly. The effect of temperature, deposition solution and cerium ion amount on the morphology and physical properties of hematite films are characterized.

This study demonstrated the electrochemical deposition of Mn-doped ZnO films under hydrothermal conditions at 130°C in 50% v/v DMSO-H2O mixture. X-ray diffraction analysis showed that the deposition of the ZnO structures was along (002) direction. However, the presence of Mn2+affected the thickness of ZnO structures and we believe that the interaction of Mn2+with the nonpolar surface of ZnO restricts lateral growth. Mn appears in the mixed oxide state in ZnO lattice. The photoluminescence spectra of the films show only UV emission indicating high crystal quality. The blueshift of the UV emission is observed after the introduction of Mn impurity into the ZnO lattice. The surface morphology, lattice structure, Mn content, chemical binding characteristics, and optical properties of the deposits were examined by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and photoluminescence spectroscopy, respectively.