关键词: TiO2纳米管, 阳极氧化, 钛酸锂纳米管

Abstract: As a critical component in lithium-ion battery technology, lithium has witnessed exponentially growing demand in renewable energy systems, driven by global decarbonization initiatives. Notably, lithium titanate, serving as an advanced lithium-ion sieve, demonstrates exceptional potential for selective lithium extraction from multicomponent brine systems containing competing cations such as Na+ and Mg2+, particularly due to its superior structural stability compared to manganese-based counterparts. In this study, hierarchically structured lithium titanate nanotube arrays with tunable surface porosity and enhanced interfacial adhesion were engineered via a multi-step synthesis protocol integrating anodic oxidation with lithiation annealing. Using titanium wire as the raw material and ethylene glycol as the electrolyte, TiO2 nanotube arrays were fabricated by controlling anodic oxidation voltage, fluoride ion concentration, and oxidation time. The lithium ion sieve was subsequently obtained through lithiation annealing and acid treatment. Experimental results demonstrated that nanotube arrays with uniform morphology and strong interfacial adhesion were obtained under optimized conditions: anodization voltage of 40 V, NH4F mass fraction of 0.5wt%, oxidation duration of 3 h, and a subsequent 5-minute 10 V potential reduction treatment. Following lithiation annealing, lithium titanate nanotubes were successfully synthesized. Acid etching increased the average pore size from 50 nm to 65 nm, while SEM and XPS analyses confirmed the retention of TiO2 nanotube morphology in the ion sieve and the successful fabrication of titanate nanotube arrays. This anodization-lithiation synergistic strategy enabled the construction of titanate-based nanotube arrays, offering valuable insights for developing next-generation high-efficiency lithium extraction materials.

Key words: TiO2 nanotubes, anodic oxidation, lithium titanate nanotubes