Voltamperometric study of the titanium IV–oxalate complexes

Deposition of thin TiO2 layers on platinum by means of cyclic voltammetry of selected complex Ti(IV) media leading to anatase

“…In aqueous solutions titanium(IV) forms unidendate 1:1 or 1:2 complexes with oxalate ions when total concentration of titanium does not exceed 0.02 mol/dm 3 [12]. The equilibrium constant of reaction (16) is 2.1 × 10 +5 , which means that even at a low excess of oxalate ions, titanium exists nearly in 100% as Ti(OH) 2 (C 2 O 4 ) 2 2− at pH in the range (2.5, 3.5).…”

Application of the Bismuth Film Electrode for Voltammetric Determination of Titanium Using Ti(IV)‐Oxalate‐Chlorate Catalytic System

“…At small concentrations and in acidic solutions, Ti(IV) formed 1 : 1 and 1 : 2 complexes with oxalate ions. These complexes were reduced to Ti(III)-(oxalate) 2 at mercury drop electrodes [16,17]. During the catalytic reaction, Ti(III)-(oxalate) 2 , formed at the electrode -solution interface, was oxidized by chlorate ions to its previous form, i.e.…”

“…Well-defined voltammograms of this catalytic system were applied for the determination of titanium traces in water [9,10], pure phosphorus [11], steel [12], copper alloys [13], solar-grade silicon [14] and pure quartz [15] carried out by means of different voltammetric techniques. The reduction mechanism of Ti(IV)-oxalate was discussed exhaustively in previous papers [16,17] and the mechanism of catalytic reaction in the presence of chlorate ions was reported in detail in [18,19].…”

Process of the catalytic reduction of Ti(IV) in oxalate–chlorate media

“…For a total oxalate concentration greater than 0.05 M and for pH less than 1.6 the contribution of the reduction of S 1 on the response obtained in square wave voltammetry (SWV) at the mercury electrode with pulse durations greater than 5 ms, becomes negligibly small and then only the peak of S 2 is observed before the proton discharge. However, because of the slow chemical reaction between S 1 and S 2 , the current may present a pronounced kinetic character [1,2].…”

“…Its intensity depends essentially on the bulk concentration quotient K = [S 1 ]/[S 2 ]. At constant ionic strength and pH, K is inversly proportional to the concentration of oxalate ions [1].…”