Indium-Doped Rutile Titanium Oxide with Reduced Particle Length and Its Sodium Storage Properties

Hiroyuki Usui; Yasuhiro Domi; Thi Hay Nguyen; Yuri Tanaka; Hiroki Sakaguchi

doi:10.1021/acsomega.0c01623

Indium-Doped Rutile Titanium Oxide with Reduced Particle Length and Its Sodium Storage Properties

ACS Omega. 2020 Jun 16;5(25):15495-15501. doi: 10.1021/acsomega.0c01623. eCollection 2020 Jun 30.

Authors

Hiroyuki Usui^{1

2}, Yasuhiro Domi^{1

2}, Thi Hay Nguyen^{3

2}, Yuri Tanaka^{3

2}, Hiroki Sakaguchi^{1

2}

Affiliations

¹ Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, 4-101 Minami, Koyama-cho, Tottori 680-8552, Japan.
² Center for Research on Green Sustainable Chemistry, Tottori University, 4-101 Minami, Koyama-cho, Tottori 680-8552, Japan.
³ Course of Chemistry and Biotechnology, Department of Engineering, Graduate School of Sustainability Science, Tottori University, 4-101 Minami, Koyama-cho, Tottori 680-8552, Japan.

Abstract

We hydrothermally synthesized In-doped rutile TiO₂ particles in an anionic surfactant solution and investigated the influences of In doping and the particle morphology on the Na⁺ storage properties. The solid solubility limit was found to be 0.8 atom % in In-doped TiO₂. In the case where no surfactant was used, the best anode performance was obtained for 0.8 atom % In-doped TiO₂ electrode by the benefits of three doping effects: (i) expanded diffusion-path size, (ii) improved electronic conductivity, and (iii) reduced electron charge density in the path. Further enhancement in the performance was achieved for the In-doped TiO₂ with a reduced particle length by the synthesis in the surfactant solution. This electrode exhibited a better cycle stability and maintained a high discharge capacity of 240 mA h g^-1 for 200 cycles. The reason is probably that Na⁺ can be inserted in the inner part of TiO₂ particles because of its reduced particle length.