Materials synthesis: A typical preparation procedure of LHTO-pre consists of two steps. i) TiO 2 powder and concentrated NaOH solution were mixed and had a hydrothermal reaction at 150 °C for several hours, followed by ion substitution of Na + with H + in 0.5 M HNO 3 solution for several hours to obtain hydrogen trititanates (denoted as HTO). ii) For chemical lithiation, a certain concentration of LiOH solution and hydrogen trititanates were sealed into an autoclave and heated at 150 °C for 12 h. The hydrothermal product was washed with deionized water and dried at 70 °C, and the LHTO-pre powder was obtained. LHTO was obtained by a 2 h-thermal-treatment of LHTOpre under vacuum at 200 °C.