Lyotropic Liquid Crystalline Mesophase of Sulfuric Acid-Nonionic Surfactant Stabilizes Lead(II) Oxide in Sulfuric Acid Concentrations Relevant to Lead Acid Batteries

Can Berk Uzundal; Fadime Mert Balci; Burak Ulgut; Ömer Dag

doi:10.1021/acsomega.7b00833

Lyotropic Liquid Crystalline Mesophase of Sulfuric Acid-Nonionic Surfactant Stabilizes Lead(II) Oxide in Sulfuric Acid Concentrations Relevant to Lead Acid Batteries

ACS Omega. 2017 Jul 20;2(7):3785-3791. doi: 10.1021/acsomega.7b00833. eCollection 2017 Jul 31.

Authors

Can Berk Uzundal¹, Fadime Mert Balci¹, Burak Ulgut¹, Ömer Dag¹

Affiliation

¹ Faculty of Science, Department of Chemistry and UNAM-Institute of Materials Science and Nanotechnology, Bilkent University, 06800 Ankara, Turkey.

Abstract

Concentrated sulfuric acid (SA) and nonionic surfactant (C₁₂H₂₅(OCH₂CH₂)₁₀OH, C₁₂E₁₀) form lyotropic liquid crystalline (LLC) mesophases in a broad range of SA concentrations; the SA/C₁₂E₁₀ mole ratio may vary from 2 to 11 in the LLC mesophases in the presence of a small amount of water. The mesophase is hexagonal at low SA concentration and cubic at higher concentrations. Three different compositions were prepared (one hexagonal and two cubic) with the SA/C₁₂E₁₀ mole ratio of 2.5, 6, and 9, denoted as 2.5LC, 6LC, and 9LC, respectively. They all display electrochemical SA activity in Pt and Pb systems. Most interestingly, they show the electrochemical formation of stable PbO species in a deeply acidic medium as evidenced by the X-ray diffraction, cyclic voltammetry, and linear sweep voltammetry experiments. The preferable properties of PbO over PbSO₄ for lead acid batteries (LABs) make it uniquely positioned as a superior gel electrolyte for the LABs that would mitigate sulfation.