%0 Journal Article %A Liu, Jinlong %A Wang, Zhenyu %A Lu, Zhouguang %A Zhang, Lei %A Xie, Fangxi %A Vasileff, Anthony %A Qiao, Shi-Zhang %D 2019 %T Efficient Surface Modulation of Single-Crystalline Na2Ti3O7 Nanotube Arrays with Ti3+ Self-Doping toward Superior Sodium Storage %U https://acs.figshare.com/articles/journal_contribution/Efficient_Surface_Modulation_of_Single-Crystalline_Na_sub_2_sub_Ti_sub_3_sub_O_sub_7_sub_Nanotube_Arrays_with_Ti_sup_3_sup_Self-Doping_toward_Superior_Sodium_Storage/9744989 %R 10.1021/acsmaterialslett.9b00213.s001 %2 https://acs.figshare.com/ndownloader/files/17452877 %K SIB %K Efficient Surface Modulation %K Na 2 Ti 3 O 7 %K Na 2 Ti 3 O 7 nanotube arrays %K surface modification %K electrode %K NH %K Single-Crystalline Na 2 Ti 3 O 7 Nanotube Arrays %K Superior Sodium Storage %X Although Na2Ti3O7-based anodes have been widely investigated in sodium-ion batteries (SIBs), their Na+ storage properties especially high-rate capability and long-term cycling durability are far from practical application, because of their intrinsic low conductivity and unsatisfied Na+ diffusion resistance. Here, we report the surface engineering of Na2Ti3O7 nanotube arrays grown in situ on Ti foil through a hydrothermal method and subsequent NH3-assisted calcination. Benefiting from the effective surface modification, the as-derived free-standing electrode possesses highly crystalline surface with favorable Na+ diffusion kinetics and self-incorporation of abundant Ti3+ for improved electronic conductivity. These features enable the electrode to achieve remarkable reversible capacity (237.9 mAh g–1), ultra-high rate capability (88.5 mAh g–1 at 100 C = 17.7 A g–1), and excellent cycling stability (92.32% capacity retention at 50 C after 5000 cycles), which are superior to the counterpart without surface modification, as well as almost all Na2Ti3O7-based anode materials reported so far for SIBs. The outstanding electrochemical performance demonstrates the feasibility of proposed surface modulation in designing more efficient electrode materials for energy storage. %I ACS Publications