Electrodeposition of PbO2–TiO2 Nanocomposite Materials from Suspension Electrolytes

Abstract

UDC 541.138 A. B. Velichenko, V. A. Knysh, T. V. Luk'yanenko, and N. V. NikolenkoIt was shown that the presence of titanium dioxide nanoparticles with an average size of 14 nm in methanesulfonate electrolytes leads to acceleration of the electrolytic deposition and crystallization of lead dioxide. It was established that the process results in the formation of PbO 2 -TiO 2 nanocomposites the composition and structure of which depend on the composition of the suspension electrolyte and the hydrodynamic conditions of electrodeposition.On account of the simplicity of its production, its high corrosion resistance, and its catalytic activity lead has found widespread use in batteries and also as active layer in dimensional stable anodes (DSA) used in the production of strong oxidizing agents and for electrochemical destruction of toxic organic substances that contaminate the environment [1]. Here, without changing the main characteristics of PbO 2 , it is possible to increase its electrochemical activity considerably by modification with various ions [2], surfactants, polyelectrolytes [3], and particles of oxides from the suspension electrolytes [4][5][6][7][8][9][10][11]. The last case is of greatest interest not only because the electrocatalytic characteristics can be substantially improved through the formation of a composite coating but also because the internal stresses of the deposits are reduced, making it possible to create a dimensional stable anode with a satisfactory service life. As shown earlier [4,7], the most promising electrolytes for the production of composites with TiO 2 nanoparticles are nitrate suspension electrolytes, which have aggregate stability and do not require forced agitation during electrodeposition of the coating. At the same time on account of the presence of nitrate ions in the solution it is not possible to produce coatings with satisfactory mechanical characteristics having a thickness of more than 100 ìm. For this reason in the present work the possibility of electrodepositing PbO 2 -TiO 2 nanocomposite materials from methanesulfonate electrolytes was examined. Earlier [5,6] it was shown that PbO 2 coatings with a thickness of up to 2 mm and with satisfactory mechanical properties can be produced from such electrolytes, but there are no published data about the possibility of creating stable suspension solutions based on them or about the composition and characteristics of the obtained PbO 2 -based materials. EXPERIMENTALAs base electrolytes we used solutions with the following compositions, M: nitrate, Pb(NO 3 ) 2 0.1, HNO 3 0.1, methanesulfonate, CH 3 SO 3 H 0.1, Pb(CH 3 SO 3 ) 2 0.1. Platinized titanium was used as substrate for the production of the 0040-5760/16/5202-0127