Electrode materials based on titanium dioxide modified with zinc ions and gold nanoparticles, synthesized by sol-gel method, were used to determine the concentration of Cu (II) in liquids by stripping voltammetry method. Determination of Cu (II) was done using background solutions based on 0.4 M formic acid and ammonium acetate buffer (pH = 7.5) using the standard addition method with a potential scanning speed of 50 mV•s-1. The solution was stirred during the preliminary electrolysis at a potential of -1400 mV (vs silver-chloride reference electrode) for 120 seconds and then the potential was scanned from -1200 mV to + 200 mV. It is shown that the background solution based on ammonium acetate buffer provides a higher sensitivity and a good selectivity of peaks for the determination of copper compared to the background solution based on formic acid. Determined that value of the analytical signal of copper in the studied model solutions based on ammonium acetate and formic acid is proportional to the concentration of copper ions in the solution. To increase the selectivity of stripping voltammetry method in determining copper concentrations in solutions, an inversion spectral photoelectrochemical method was proposed, the essence of which is preliminary electroconcentration of the elements under investigation in the cathode potential region and subsequent measurement of the spectral photoelectrochemical characteristics of electroconcentration products. It has been found that in solutions of 1M ammonium acetate containing Cu2+ ions, the cathodic polarization of TiO2-based photoelectrode leads to the appearance of a cathode photocurrent and the values of photocurrent quantum yield increase with increasing content of copper ions in the solution. The spectral sensitivity of the surface layer corresponds to the absorption spectrum of Cu2O. The sensitivity of stripping voltammetry method to copper Cu (II) using the materials studied was 0.3 mg•l-1. It is shown that the inversion photoelectrochemical method is promising in the selective determination of copper concentration in liquids.
Mercer J. F. B. The molecular basis of copper-transport diseases. Trends Mol. Med. 2001. 7: 64.
Yin K., Wu Y., Wang S., Chen L. A sensitive fluorescent biosensor for the detection of copper ion inspired by biological recognition element pyoverdine. Sensors and Actuators B: Chemical. 2016. 232: 257.
Vydra F., Shtulik K., Yulakova E. Inversion voltammetry Moscow : Мir, 1980). [in Russian].
Brainina Kh.Z., Stozhko N. Yu., Aleshina L.V., Lipunova G.N. Mercury-free electrode for the determination of amalgam-forming elements by stripping voltammetry method. Journ. Anal. Chem. 2003. 58(10): 1078. [in Russian].
Brainina Kh.Z., Stozhko N.Yu., Belysheva G.M., Inzhevatova O. V., Kolyadina L.I. Determination of heavy in untreated dry wines by anodic stripping voltammetry with modified thick-film electrode. Anal. Chim. Acta. 2004. 14(2): 227.
Linnik O., Smirnova N., Korduban O., Eremenko A. Gold nanoparticles into Ti1-xZnxO2 films: Synthesis, structure and application. Materials Chemistry and Physics. 2013. 142: 318.
Smirnova N., Vorobets V., Linnik O., Manuilov E., Kolbasov G., Eremenko A. Photoelectrochemical and photocatalytical properties of mesoporous TiO2 films modified with silver and gold nanoparticles. Surf. And Interface Analysis. 2010. 6-7(42): 1205.
Brandt I. S., Tumelero M. A., Pelegrini S., Zangari G., Pasa A. A. Electrodeposition of Cu2O: growth, properties, and applications. J.Solid State Electr. 2017. 21: 1999.
Suhaimi S., Shahimin M. M., Alahmed Z. A., Chysky J., Reshak A. H. Materials for enhanced dye-sensitized solar cell performance: Electrochemical application. Int. J. Electrochem. Sci. 2015. 10(4): 2859.
Zhao W.-W., Xu J.-J., Chen H.-Y. Photoelectrochemical DNA Biosensors. Chem. Rev. 2014. 114(15): 7421.
Cooper J. A., Wu M., Compton R. G. Photoelectrochemical analysis of ascorbic acid. Anal. Chem. 1998. 70: 2922.
Dong D., Zheng D., Wang F.-Q., Yang X.-Q., Wang N., Li Y.-G., Guo L.-H., Cheng J. Quantitative Photoelectrochemical Detection of Biological Affinity Reaction: Biotin−Avidin Interaction. Anal. Chem. 2003. 76: 499.
Sun B., Dong J., Shi W. J., Ai S. Y. A hierarchical charge transport cascade based on W-Bi2S3/poly(thiophenyl-3-boronic acid) hybrid for robust photoelectrochemical analysis of subgroup J of avian leukosis virus. Sensor Actuat. B-Chem. 2016. 229: 75.
Wen G., Wen X., Choi M. M. F., Shuang S. Photoelectrochemical sensor for detecting Hg2+ based on exciton trapping. Sensor Actuat. B-Chem. 2015. 221: 1449.
Hsu Y.-K., Yu C.-H., Chen Y.-C., Lin Y.-G. Hierarchical Cu2O photocathodes with nano/microspheres for solar hydrogen generation. RSC Adv. 2012. 2(32): 12455.