Herein, we report a systematic experimental and theoretical study about a wide-ranged band gap tuning of protonated titanate nanotubes H₂Ti₃O₇ (Ti-NT) by an easy ion-exchange method using a low concentration (1 wt%) of transition metal cations. To characterize and describe the effect of M doping (M = Cu²⁺, Ni²⁺, Co²⁺, and Fe³⁺) on the electronic, optical and structural properties, semiconductors were analyzed by a combination of experimental methods and density functional theory (DFT) calculations. The nanotube band gap can be modified from 1.5 to 3.3 eV, which opens the possibility to use them in several optoelectronic applications such as photocatalysts under solar light irradiation.

中文翻译：

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调整 M 掺杂钛酸盐纳米管（M = Fe、Co、Ni 和 Cu）的带隙：实验和理论研究

在此，我们报告了一项关于通过使用低浓度（1 wt%）的简单离子交换方法对质子化钛酸盐纳米管 H ₂ Ti ₃ O ₇ (Ti-NT) 进行宽范围带隙调谐的系统实验和理论研究。过渡金属阳离子。表征和描述 M 掺杂的影响（M = Cu ²⁺、Ni ²⁺、Co ²⁺和 Fe ³⁺) 在电子、光学和结构特性方面，结合实验方法和密度泛函理论 (DFT) 计算对半导体进行了分析。纳米管的带隙可以从 1.5 eV 修改到 3.3 eV，这为将它们用于多种光电应用（例如在太阳光照射下的光催化剂）中提供了可能性。