Electrophoretic Deposition on Anodes from Aqueous Titania Suspensions with Titanate Solution

Abstract

Titanate aqueous solution (TTIP-Lac) prepared by direct reaction of titanium tetraisopropoxide (TTIP) with lactic acid (Lac) in water shows characteristics of a polyanion and acts as a dispersant for preparing titanate suspension. Electrophoretic deposition (EPD) of aqueous titania suspensions was investigated with TTIP-Lac as a dispersant and hydroquinone (HQ) as an effective additive for bubble-free EPD of the aqueous system. The oxygen produced electrolytically by the EPD process at basic pH would be consumed by the chemical oxidation of HQ to quinone (Q). Bubble-free titania depositions were fabricated on anodes by EPD. A fired density with 99% theoretical density was obtained.

Anodic aqueous electrophoretic deposition of titanium dioxide using carboxylic acids as dispersing agents

“…As citric and oxalic are weak acids, high concentrations of these reagents were necessary to achieve low pH levels. It is likely that the high levels of protonated citric and oxalic groups in aqueous solution lead to a decrease in the volume of the liquid sphere which moves along with the particle in suspension and thus allows the particles to approach each other, facilitating agglomeration 27,32,33 .…”

“…EPD is generally followed by a densification process through thermal treatment. The process of EPD has been used with suspensions of TiO 2 in the past [25][26][27] . EPD synthesis of materials has several advantages:…”

Triethanolamine as an Additive in the Electrophoretic Deposition of TiTe₃O₈ Thick Films

“…Polyacrylic acid and polyethylene glycol [14] have been used for dispersing ZnO-Al 2 O 3 mixed powders in water. Hydroquinone [15] and iodine [16] were separately added in water and ethanol for the fabrication of TiO 2 films. Citric acid and polyvinyl pyrrolidone (PVP) [17] were added to acetone for EPD of LiNi 0.5 Mn 1.5 O 4 and carbon black thick films, for lithium batteries.…”