نشریه شیمی کاربردی روز
پیاپی 55 (تابستان 1399)

4,4'-Diaminodiphenyl ether-2,2'-disulfonic acid (ODADS) as a sulfonated diamine was fabricated by direct sulfonation of diamine, 4,4'-diaminodiphenyl ether in the presence of fuming sulfuric acid as the sulfonating agent. Additionally, a xanthene-containing diamine monomer was prepared in four steps, by the condensation of β-naphtol and 4-nitrobenzaldehyde in the presence of p-toluenesulphonic acid catalyst, reduction of the nitro intermediate, the nucleophilic substitution reaction of amine and 3,5-dinitrobenzoyl chloride, and subsequent reduction of the dinitro compound. The diamine monomer could be obtained in quantitative yield. Then, a series of new sulfonated polyimide/silica nanocomposites with different percentages of silica have been successfully synthesized through the in situ formation of silica within a polymer matrix via sol-gel process. Poly(amic acid) solution is prepared from 1,4,5,8-naphthalenetetracarboxylic dianhydride, ODADS and nonsulfonated diamine, 3,5-diamino benzoyl amino phenyl-14H-dibenzo[a,j]xanthene in N-methyl-2-pyrrolidinone solvent. Finally, the nanocomposites films were obtained by the hydrolysis-polycondensation of silica precursors (3-aminopropyl)triethoxysilane (APTES) and tetraethoxysilane (TEOS) in poly(amic acid) solution and then thermally imidized to form polyimide/silica nanocomposites. The chemical and morphological structure of the hybrid nanocomposites were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, and transmission electron microscopy. The electrical conduction of materials was measured by potentiometer. The results of TEM show that the silica particles are well dispersed in the copolyimide matrix with particle size between 50 and 70 nm in diameter. Thermogravimetric analysis results indicated that the addition of silica into the sulfonated polyimide matrix was increased the thermal stability of the resulted nanocomposites owing to the enhanced interaction and good dispersion the silica into the polyimide matrix. The prepared nanocomposites were exhibited good water stability as well as great electrical conduction.

In this paper, the interaction between methyl ethyl ketone and some types of alcohols (2-propanol, 2- butanol, 2-pentanol, 2- hexanol and 2-heptanolol) was studied using an empirical method along with Kirkwood-Buff integrals and the of preferential solvation phenomenon. For binary systems including methyl ethyl ketone with 2-alkanol, the parameters Gii, Gjj, Gij, δii, δjj, and δij were calculated at 298.18 K and interpreted based on the structure and type of bond formed in solutions. The results were discussed based on molecular interactions and the effect of carbon chain lengths of alcohol. In general, it can be concluded that the interactions in the mixtures are weaker than the pure state, and with the increase in the length of the alcohol chain, these interactions become weaker because, as the chain length increases, the nonpolar part of the molecule increases. The results obtained from the Kirkwood-Buff integrals were confirmed using experimental values of excess molar volumes.

The reaction of [PtMe2(4,4'-Me2bpy)] (4,4'-Me2bpy = 4,4'-dimethyl-2,2'-bipyridine) with [SnMe2(NCS)2] in a 1:1 mole ratio led to the formation of [PtMe2(SnMe2NCS)(SCN)(4,4'-Me2bpy)] via dissociation of the Sn-NCS bond. The product has been fully characterized by elemental analyses, UV-Vis, IR, (1H, 13C, 119Sn, 195Pt, HHCOSY, and HSQC) NMR spectroscopy. On the basis of NMR data, the Pt(IV) product of the each contains almost exclusively the kinetic trans isomer corresponding to that of trans oxidative addition of SnMe2(NCS)2. The IR spectrum of complex displays characteristic sharp absorptions resulting from the SCN and NCS groups of Pt-SCN and Sn-NCS units. In vitro anticancer activity of three analogues complexes trans-[PtMe2(SnMe2NCS)(SCN)(4,4'-Me2bpy)], trans-[PtMe2(SnMe2Cl)(Cl)(4,4'-Me2bpy)], and trans-[PtMe2(SnEt2Cl)(Cl)(4,4'-Me2bpy)] were tested against human breast carcinoma (MDA-MB-468) and glioblastoma multiforme (U-87MG) cell lines. The results show that trans-[PtMe2(SnEt2Cl)(Cl)(4,4'-Me2bpy)] revealed higher cytotoxic effect towards both cancer cell lines, which shows the significant role of the alkyl group.

In this research, the inhibition effect of thionine (Thn) and its synergistic effect with Zn2+ on the corrosion of a carbon steel A106 sample in 0.5 M sulfuric acid has been investigated using electrochemical potentiodynamic polarization technique and weight loss tests. Using Tafel polarization plots and corrosion rate calculations, it was revealed that Thn act as an effective inhibitor. It was found that the results of weight loss test and polarization method are in good agreement. The synergistic effect of zinc ions on the corrosion inhibition of steel in the presence of various concentrations of Thn was investigated, too. The addition of zinc ions enhances the inhibition efficiency considerably. Maximum inhibition efficiency was achieved about 97% for a system containing 20 ppm Thn and 16.7 mM Zn2+. The presence of zinc ions increases the degree of surface coverage. The synergism parameters "S", calculated from surface coverage, are found to be larger than unity for some of Thn concentrations. Thn behaved as a mixed type inhibitor in H2SO4 solution. It was investigated too, that the adsorption of Thn on the metal surface was obeyed Langmuir adsorption isotherm and adsorption was performed spontaneously. Investigating the adsorption mechanism proved that it is possible to form a complex between the initial Zn2+ layer on the steel surface with the protonated form of thionine.

An efficient synthesis of 3-aminoimidazo[1,2-a]pyridines via three-component reaction from aromatic aldehydes, 2-aminopyridines and isonitriles at room temperature in water/2,2,2-trifluoroethanol two-phase systems is described. In this methodology equivalent or better yield was obtained in the two-phase systems when compared to pure 2,2,2-trifluoroethanol for reaction. The use of the two-phase system also reduces the consumption of CF3CH2OH by 75% leading to a significant reduction in cost as well as toxicity of the reaction media. The strong hydrogen bond donation properties can also eliminate the need for Lewis acid catalyst, further simplifying the procedure. High yield, short reaction time, simple work up without need to column chromatography and use of mild and environmental friendliness conditions are some of benefits of the present method in synthesis of this biologically compounds.

In this research, anodizing method at constant temperature of 0oC and in constant current in the phosphoric acid electrolyte was used to synthesize the nano-porous alumina templates with desired pore diameter. A new system for controlling temperature as well as for Creation homogeneous conditions in electrolyte solution has been used. Designing experiments and identifying important variables on the diameters of synthesized alumina pores was carried out using the central composition design and the response surface method was used to evaluate the interaction of the parameters and determine their importance on the diameter of the synthesized porous anodic alumina pores. The intensity of the applied current, the electrolyte concentration and the duration of the anodizing was considered as variable parameters. FE-SEM images were used to determine the diameter of the pores. The main purpose of this research is to provide a model for determining the appropriate laboratory conditions for the synthesis of nano-porous anodic alumina templates with desired pores diameter.

Two new polymeric compounds of cadmium acetate and Schiff-base ligand 1,2-bis(1-(pyridine-4-yl)ethylydine)hydrazine, L, [Cd(OAc)2(L)]n ,(1) and [Cd(OAc)2(L)(H2O)]n , (2) were synthesized and characterized by single crystal X-ray diffraction analysis. Structural analysis reveals that both compounds were crystallized in monoclinic crystal system with P21/c and I2/a space group respectively. Coordination polymer 1 was synthesized by solvent evaporation method in dimethyl sulfoxide and has one-dimensional ladder like structure. Coordination polymer 2 was prepared by solvent diffusion method in the mixture of methanol and water solvent and its crystal structure was assembled from one-dimensional linear chains. Also the influence of effective interactions in the crystal packing of prepared compounds and the value of their contributions were investigated by Hirshfeld surface analysis.

A new bidentate Schiff base ligand was derived from the 2:1 molar condensation of ferrocenecarboxaldehyde with 3,4-diaminobenzophenone. Palladium, nickel and copper complexes were obtained by the reaction of the bidentate Schiff base ligand with palladium(II) acetate, nickel(II) acetate tetrahydrate and copper(II) acetate monohydrate in 1:1 molar ratio. In palladium, nickel and copper complexes the ligand was coordinated to metals via the imine N atoms. The fluorescence properties of the Schiff base ligand and its complexes were studied in DMSO. The molar conductivity values of complexes in acetone solvent implied the presence of non-electrolyte species. Electrochemical properties of the ligand and its metal complexes were investigated in the DMSO solvent at the 100 mVs−1 scan rate. The ligand and its metal complexes showed both reversible and irreversible processes at this scan rate. The products were characterized by FT-IR, 1H NMR, UV-Vis spectroscopies, elemental analysis, and conductometry.

Stipa capensis, the Mediterranean needle-grass, is an annual grass of the genus stipa, in the Poaceae family. It is normal found in the Persian Gulf desert ad semi-desert biome. This plant is indigenous to the Fars, Khuzestan, and west of Iran. In traditional medicine, stipa capensis have been used for illness related to the Nerve system problems and gastric discords. The goal of this study is to identify and characterize the phytochemical compound present in this valuable medicinal plant. This is the first report of the presence of phytochemical in stipa capensis. Stipa capensis is commonly known as Bahman in Iran. The leaves of the plant Stipa capensis was collected from Masjede-Soleiman, Khuzestan, Iran in March, 2015.Basic phytochemical screening from the aerial parts of stipa capensis revealed the presence of terpenoids and steroids. The powdered sample was extracted and was further fractionated successively with n-hexane and methanol.The nonpolar fraction was subjected to column. The separated constituents were subjected to LC-MS and GC-MS study. The spectrum of the unknown compounds was compared with the spectrum of the component stored in the NIST (National Institute Standard and Technology) library.The results pertaining to LC-MS analysis led to the identification of number of terpenes from fraction of the hexane extract of Stipa capensis.This is the first report of the screening and isolation of phytochemical in stipa capensis. This study reports the isolation and identification of terpenoid extracted from stipa capensis on fraction 1and 4 isolated that led to isolation of terpenoid compounds (carotenoids, steroids, cardiac glycosides and prenol lipids.)

In this paper, a new magnetic ion imprinted polymer nanoparticles was synthesized and utilized for the selective and rapid extraction, preconcentration and determination of trace amounts of Cd(II) ion in water, soil and food samples. The parameters affecting preconcentration like pH, adsorption time, amount of sorbent, elution solvent, eluent volume and concentration and desorption time were optimized. Following the sorption and elution steps, Cd(II) ion was quantified by flame atomic absorption spectrometry. The limit of detection (LOD) and the relative standard deviations (RSDs) were 0.3 μg L-1 and 3.45% -5.63% (inter-day and intra-day), respectively. The sorption capacity of ion imprinted polymer was 66.35 mg g-1 for Cd(II) ion. Finally, the proposed method was applied for determination of Cd(II) ion in water, soil and food samples.

Silica- supported boron trifluoride nanoparticles (BF3. SiO2 NPs) was prepared and used as a mild green solid acid catalyst for the synthesis of pyrano[2,3-d]pyrimidine derivatives from the reaction of aromatic aldehydes with ethylcyanoacetate and barbituric acid in ethanol. The reaction was efficiently promoted by BF3. SiO2 NPs and the heterogeneous catalyst was recycled for three runs in this reaction without losing its catalytic activity. Reusable and eco-friendly catalyst, simple work up procedure, easy separation of product from reaction mixture, safe and clean reaction giving high yield of the corresponding pyrano[2,3-d] pyrimidine in a short time, are some advantages of this protocol.

In this research, with the aim of improve the loading efficiency and particle size Chitosan (CS)-Montmorillonite (MMT) nanocomposite were prepared using a ionic gelatinization method for controlled delivery of curcumin. Different formulation and processing variables (Cs concentration, MMT percentage, surfactant concentration, drug amount and sonication time) were used to determine the optimal formulation. Polysaccharide concentration, surfactant concentration and sonication time had higher effect on particle size. MMT addition significantly enhanced the entrapment efficiency of Curcumin and the optimal value for MMT was 3 w%. Also, the increase in drug amount (mg/ml) resulted in the increase in entrapment efficiency. Physicochemical characteristics of optimal formulation were determined in terms of entrapment efficiency, release profile, Size, Zeta potential, surface morphology and FTIR spectra. Formulation 2A with a particle size of 23.8-31.3 nm, a loading efficiency of 93.71% and a Zeta potential of -73.38 ± 0.88 m were selected as the optimal formulation. SEM and FTIR studies revealed spherical morphology and lack of chemical interaction between nanosystem and drug. The in vitro release study showed that Curcumin had a slow and sustained release profile at basic pH 7.4, which significantly increased at acidic pH of 4.5. The maximum release of the drug from nanocomposite was 80% at 37°C, pH 4.5 after 24 hours.

The ZnS/CuFe2O4 magnetic hybrid nanocatalyst was synthesized for the first time by a simple procedure. Investigation and characterization of this catalyst were carried out using energy-dispersive X-ray spectroscopy (EDX), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and vibrating sample magnetometer (VSM) analyses. Synthetic nanoparticles were used as a magnetic and heterogeneous catalyst for the one-pot synthesis of 2-amino-3-cyano-4H-pyran derivatives with condensation of dimedone, aromatic aldehydes and malononitrile in ethanol at room temperature. The reported method has advantages such as mild conditions, good yields, simple separation of products from the reaction mixture and the use of biocompatible solvent and inexpensive catalyst. Nanocatalyst ZnS/CuFe2O4 was easily separated from the reaction using an external magnetic field and reused several times in reactions without appreciable reduction in catalytic activity.

Titanium dioxide is one of the most important minerals with various industrial applications. Extensive research has been carried out to synthesize this material from the past and is also ongoing. At present, despite the high consumption of this material, it does not have internal production and the needs of the country’s industries are being met by import of this product. Considering the country’s richness in terms of having Titanium mines, research has begun to find the conditions for the production of Titanium dioxide from Ilmenite minerals. In this research, Ilmenite concentrate of Kahnouj region in Kerman province was used to obtain Titanium dioxide. This concentrate contains 43% TiO₂ which is a low-grade concentrate. In this project, the production of Titanium dioxide from Ilmenite minerals with two methods of Chloride process and Alkalydecomposition process was investigated. The Alkaly decomposition process involves the steps of decomposition, acid leaching, sediment washing and calcination. Investigating and studying the various Titanium processing methods showed that the Alkally decomposition process has more advantages in terms of moderate operating conditions than other methods. The Titanium dioxide obtained in this study was made by a nano satellite ball mill. The chemical composition of Ilmenite concentrate was investigated by X-ray Fluorescence analysis (XRF). The structural properties and the size of the Titanium dioxide nanoparticles investigated by Furier Transform Infra-Red spectroscopy (FT-IR), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy-Disperssive X-ray spectroscopy (EDX).

In this work, the inhibition performance of 5-(3, 4, 5-Trimethoxyphenyl)-2H-tetrazole on mild steel corrosion was investigated in 1 M HCl solution. Scanning electron microscopy (SEM), electrochemical impedance spectroscopy(EIS) and polarization were used to determine its inhibition effects. Different concentrations of the inhibitor and temperatures effect were investigated in 1 molar acid chloride solution. Polarization studies showed that the inhibitor affected mild steel in 1 M HCl solution by two types of interaction, chemisorption and physisorption. The Gibbs free energy of this inhibitor was -29.91 kJ.mol-1. Adsorption isotherm investigation of the inhibitor on mild steel proved that the adsorption of the inhibitor obeys the Langmuir adsorption isotherm. The results showed that increasing the inhibitor concentration up to 300 ppm increased the inhibition percentage up to 90%. The impedance results indicated increasing of the corrosion resistance in the presence of the inhibitor more than 10 times compared to the absence of the inhibitor.

In recent years, the growing public awareness of environmental issues has revealed the fact that natural resources in the world are declining and there is limited capacity to manage the volume of waste generated by human activities. Nowadays, the recycling of polymeric materials, especially polyurethane foam, is very important due to its extensive usage in the most of the industrial fields and, in parallel, the production of massive amount of wastes. Among the various types of polyurethane waste recycling methods, the glycolysis process is considered as a chemical recovery method. Due to its ease of use and the conversion of waste into the raw materials, especially polyol, the main route is polyurethane foam recycling. The process involves split phase recycling one in which the phases consisting of upper recovered polyol composition and the lower one is containing heavy aromatic contained complex composition materials. Evidence showed that with increasing the amount of catalyst, the rate of foam dissolution increased and the urethane bonds cleavage take place in the short reaction times. In this study, various weight percentages of Mo/MgO composite catalyst is used to recover flexible polyurethane foam wastes. After complete dissolution of the foam particles, the chemical structure of recovered products was identified and characterized by different spectroscopic and analytical methods, respectively. Obtained results showed the successful recycling of polyurethane wastes to the firstly used virgin poly in combination with other complicated compositions namely aromatics, unreacted reagents etc. in addition our founds shown that by increasing the weight of the catalyst led to the high recovery yields and decreases the percentage of aromatic compounds.

In this work, 4-bromo-1,2-bis[2-hydroxy-5-(4-nitrophenylazo)benzylideneamino]benzene (H2L) based on azo Schiff-base ligands was prepared from condensation reaction of 1-[3-formyl-4-hydroxophenylazo)-4-nitrobenzene and 4-bromo-1,2-diaminobenzene and characterized with several spectroscopic techniques and elemental analysis. It is well known azophenol groups in different compounds may exist in azophenol and quinone-hydrazone tautomeric forms. There are many factors such as solvent, temperature and substitution that affect equilibrium tautomeric forms. The investigation of UV-Vis spectra of H2L in DMSO and the mixture of DMSO and water showed the solvatochromism that exhibited by azo ligands may be to the effect of proton transfer or dipole moment changes in various solvents. In DMSO, an additional absorption maximum which observed at around 500 nm attributed to the existence of tautomeric form. Also, the increasing of pH and deprotonation of hydroxyl groups affect the keto-enol equilibrium in solution, so that the main absorption bonds and color solution change strongly in intensity. The investigation of UV-vis spectra of H2L in the presence of Ca2+, Cd2+, Cu2+, Co2+, Hg2+, Ag+, Pb2+, Zn2+, Na+ and Ni2+ metal ions revealed the intensity of absorbance bonds changes dramatically with the addition of all cations to the solution of ligand (generally, n→π* transition increases in intensity while π→π* transition decreases). It seems that complexation metal ions for H2L affect keto-enol equilibrium, although it is unknown that why different metal ions have one unequal effect on keto-enol equilibrium. Finally, DFT and TD-DFT calculations was done for better understanding of structure and electronic properties of ligand H2L.

The purpose of this study is to consider and compare applicability of modified chitosan nano fibers with functionalized mesoporous silica in Elecrtrospinning method for Direct Yellow 12 (D.Y.12) removal from aqueous solutions. Provided nano fibers were monitored and detected by TEM, Fe-SEM, XRD, FT-IR devices and Tensile testing. Subsequently, the effect of different operating parameters was achieving optimum condition for performing the adsorption process: such as nano adsorbent types, adsorbent dose, pH, initial dye concentration, contact time. And ultimately, finding suitable isotherms for adsorption of D.Y.12 was performed. Desirable conditions for removing by mesoporous silica chitosan nano fibers with SBA-15-NH2 adsorbent in 40 minutes contact, pH=2, the amount of adsorbent was 0.05 gr with 20 mg/l initial concentration. Also, the results have shown that D.Y.12 removal is following Langmuir and Freundlich isotherm model. The conclusions of this investigation have shown that CTS/SBA-15-NH2 nano fibers adsorb the D.Y.12 effectively and has great potential for purification of infected waste water with dyes.

In this study, a green and efficient method for the synthesis of benzoquinoline compounds has been described through the reaction of malononitrile derivatives with different aldehydes and naphthylamine in the presence of heterogeneous functionalized nanocellulose catalyst with sulphonic groups (Fe3O4@ Cellulose-OSO3H) is described. Synthesis of benzoquinoline is proceed very well in the presence of Fe3O4@ Cellulose-OSO3H under solvent-free conditions using ultrasonic waves. The Fe3O4@ Cellulose-OSO3H can be recoverd and reused at least four consecutive times under optimized conditions with a slight decrease in its catalytic activity. High to quantitative yields of the desired products, low loading of the catalyst, short reaction times at ambient temperature, reusability of the catalysts, and avoiding the use of toxic solvents are significant advantages of this green protocol.

Abstract Electrochemical determination of tert-Butylhydroquinone was investigated at surface of carbon paste electrode modified with Au nanoparticle and 1-methyl-3-octylimidazolium tetrafluoroborate as sensor. The Au nanoparticle was biosynthesized by Nettles extract and its morphological structure was characterized by TEM method. The modified electrode (carbon paste electrode modified with Au nanoparticle and 1-methyl-3-octylimidazolium tetrafluoroborate) accelerated the oxidation reaction of tert-Butylhydroquinone as food antioxidant. In the optimum condition, the linear dynamic range 5.0 nM-450µM with detection limit 1.0 nM was obtained for determination of tert-Butylhydroquinone. The fabricated sensor of was successfully used for analysis of tert-Butylhydroquinone in food samples. Keywords: tert-Butylhydroquinone, Au nanoparticle, Biosynthesis, Electrochemical sensor, 1-methyl-3-octylimidazolium tetrafluoroborate

Cobalt-aluminum layered double hydroxide was successfully prepared by mechano-chemical method. It was synthesized in a mortar by manually grinding the hydrated cobalt and aluminum nitrate salts with sodium hydroxide. According to FT-IR, XRD and BET, the synthesized sample showed characteristic of layered double hydroxides. The as-prepared Co-Al-LDH exhibited a high adsorption activity to the Methyl Orange dye. Batch adsorption experiments were carried out at room temperature under various conditions such as contact time, adsorbate mass and pollutant concentration. Langmuir and modified Freundlich isotherms were also used to investigate adsorption. The results of isotherm studies showed that adsorption of dye onto LDH fits to the modified Langmuir equation with sorption capacity of 656.96 mg/g.

Optical chemical sensors (optode) have important place in the analytical chemistry research area because of their use in different fields of human knowledge’s. The study of these sensors is also attractive since they allow us to perform in vivo analysis and in situ monitoring. Determination of nitrite ions as a potentially carcinogenic species is in the core attention of the analytical scientists to produce simple, fast, cost effective and environmental friendly approaches. In this work a new simple, low cost, and sensitive optical sensor has been developed for determination of nitrite ions based on the immobilization of saffron (Crocus sativus L.) as a natural sensing reagent on the triacetylcellulose membrane. Selective reaction of the saffron and nitrite ions in the acidic media was monitored photometrically and absorption changes in the wavelength of 440 nm were recorded as analytical signal. The influence of effective variables on the optode performance including triacetylcellulose activation process, concentration of saffron, response time and the effect of ionic strength were studied and optimized. In the optimum conditions, the sensor has good durability and a short response time with linear dynamic range of 1.010-3 – 50.0 μg mL-1 and detection limits of 7.010-4 μg mL-1. Reproduce determinations were done on the solution containing 5.0 μg mL-1 nitrite ion and RSD (n=5) of 4 % was obtained. The effects of various ions and species on the analytical signal were also studied and application of the proposed method in the determination of nitrite ion in many real samples such as tap and well water gave satisfactory results.

The present study is aimed to investigate ZIF-8 metal organic frameworks, graphene quantum Dots, and their hybrid materials (GQD@ZIF-8) in the terms of sensing heavy metals. Brilliant property of graphene quantum Dots in fluorescence emission with a high intensity and ZIF-8 with high porosity and specific surface area (as adsorbent) were great stimulants to fabricate the aforementioned sensing system. The prepared hybrid material was successfully employed for the measurement of heavy metals such as lead in aqueous samples. The concentration of lead in various samples was measured using GQD@ZIF-8 hybrid materials via the method of single parameter during the time. In order to characterize GQD@ZIF-8 hybrid materials, Scanning Electron Microscopy (SEM), Furrier Transform Infrared spectroscopy (FT-IR), and nitrogen adsorption/ desorption (BET and BJH analysis) were employed in present study. Different parameters such as time, pH, and the concentration of adsorbent were also optimized in present study. The optimized values for concentration of adsorbent, time, and pH were found to be 0.05 mg/ml, 5 min, and 5 respectively. Importantly, limit of detection (LOD) for lead was calculated as 0.86 ppm. Low amount of LOD can be attributed to high fluorescence intensity and great specific surface area of the proposed sensor. The obtained results for LOD were compared with the other existing methods for detection of lead, presented in literature. The obtained results demonstrates that the proposed hybrid material possess high potential for detection and removal of lead from real samples.

In this research, the use of ZnO thin films, as anti-reflective layers of solar cells, is presented. The thin films were synthesized through a sol-gel method and then deposited on a P-N silicon substrate using the spin coating technique. The effect of the ZnO thin films on the efficiency of a solar cell piece was then investigated. To synthesize the ZnO films, zinc acetate dihydrate was used as the precursor, monoethanolamine (MEA) was employed as the stabilizer, and 2-methoxyethanol was used as the solvent. also in order to investigate the effect of concentration of sol-gel solution in formation of ZnO nanoparticles, samples with various concentrations were prepared and after deposition, solar cell piece was fabricated. The ZnO thin films prepared were characterized using X-ray diffraction and field emision-scanning electron microscopy, and a four-point probe was used to measure the surface resistance of the sample. Moreover, to evaluate the electrical properties of the solar cell piece, first, the back and front metal connections of the solar cell were installed using the stencil silk-screen printing method and then a solar simulator was used. The obtained results indicated that the nano-structured ZnO films with hexagonal crystallites and 30-50 nm particle sizes were successfully formed on the silicon substrate. Also, the observations unraveled that the coated ZnO films could act as an anti-reflection films and improved the efficiency of silicon solar cells. In addition, the results showed that the concentration of the sol-gel solution can have a considerable effect on the efficiency of the silicon solar cell.