The Effect of Surfactants on the Properties of Colloid Precursor Li2TiO3

Abstract

A lithium titanate (Li2TiO3) precursor colloid with high stability was synthesized via a novel inorganic precipitation–peptization method using low cost titanium sulfate as a titanium source, lithium acetate as a lithium source and hydrogen peroxide as a complexing agent. The formation mechanism of the precursor sol was discussed, and the effect of the addition of triethanolamine (TEOA) and sodium dodecylbenzenesulfonate (SDBS) on the colloidal stability was investigated in detail. Samples were characterized with thermogravimetric analysis–differential scanning calorimetry (TG-DSC), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Brunnauer–Emmet–Teller (BET) analysis. The results indicate that the colloid stability is enhanced by increased dosage of TEOA and SDBS within a certain range. The best colloid stability is achieved when the amount of TEOA added is 0.75%, and the sol system can remain stable for up to 15 days, which is 7.5 times that of the precursor sol without added surfactant. The optimal amount of added SDBS is 0.125%, and the effect of SDBS on colloid stability is not as significant as that of TEOA. SDBS favors the formation of the crystal structure of Li2TiO3, while TEOA inhibits the ordered arrangement of Li+ in the main crystal layer. The sample (Li2TiO3) surface with SDBS shows a porous structure, which is conducive to the subsequent pickling treatment.