Tailored Design Ti4+ Coordination via Coplanar Carboxyl and Hydroxyl Groups Toward High Purity TiO2(B) with Ultrafast Li+ Storage

Abstract TiO 2 (B) is a promising anode material for lithium‐ion batteries (LIBs) due to its fast lithiation/delithiation kinetics, however, its thermodynamic metastable nature makes it difficult to synthesize pure phase, which significantly affects its lithium storage capability. Herein, the structural evolution from precursor to TiO 2 (B) is systematically investigated and it is revealed that the formation of high‐purity monoclinic HTO (hydrogen titanate) precursor is the key to preparing TiO 2 (B) with high purity, which can be achieved via tailored‐design the solvent structures of Ti 4+ in the precursor solution. Glycolic acid (GA) is favorable for the synthesis of high‐purity HTO, benefiting from its simplest spatial structure and coplanar carboxyl and hydroxyl groups for Ti 4+ coordination, further leading to the formation of TiO 2 (B) with a high phase purity of 98.83% that exhibits excellent rate capability (80.5% capacity retention with current densities increased from 1 to 30 C), thus making it a promising candidate for simultaneous energy and power density LIBs anode.