long‐term cycling stability is important for efficient energy storage. Herein, a simple one‐step
approach for fabricating blue TiO2 nanoparticles with oxygen vacancies is reported. Oxygen
vacancies can enlarge lattice spaces, lower charge transfer resistance, and provide more
active sites in TiO2 lattices. As a result, this blue TiO2 electrode exhibits a highly reversible
capacity of 50 mAh g− 1 at 100 C (16 800 mA g− 1) even after 10 000 cycles, which is …