Titanate nanotubes (TNTs) fabricated through microwave-assisted synthesis were examined for their ability to catalyze hydrogen production from a 20% v/v methanol solution under UV and visible light irradiation. Herein, TiO2 was used not only as the raw material for TNT synthesis but also as a reference support to compare its performance with that of TNTs. The UV–Vis spectral analyses of the TNT composites showed greater shifts toward the visible region after Pt loading than the spectra of Pt/TiO2. Moreover, using the Kubelka–Munk equation and Tauc Plot method, we determined that the direct allowed transition in TNT composites was more probable than the indirect allowed transition. The photocatalytic performances were evaluated by measuring the hydrogen production, and the experimental results showed that Pt/TNTs exhibited higher activity than Pt/TiO2. Furthermore, bare TNTs and Pt/TNTs showed lower CO generation than bare TiO2 and Pt/TiO2. As such, TNT composites enhanced the photocatalytic selectivity for H2 generation from formic acid to a greater extent than Pt/TiO2, because the kinetic diameter of CO (0.38[Formula: see text]nm) is larger than that of CO2 (0.33[Formula: see text]nm). This result may be attributed to the inability of CO to diffuse into the pores of TNTs because of the diameter difference. Also, XPS results showed negative shifts of Pt binding energies and positive shifts of Ti binding energies due to the strong metal-support interaction between Pt and TNTs. Thus, the remarkably high photocatalytic efficiency of TNT composites facilitates their application as promising photocatalysts.

中文翻译：

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载有铂的钛酸盐纳米管的微波辅助合成具有增强的选择性，用于从甲醇中光催化析氢

研究了通过微波辅助合成制造的钛酸盐纳米管 (TNT) 在紫外和可见光照射下催化 20% v/v 甲醇溶液制氢的能力。在此，二氧化钛2不仅用作合成 TNT 的原料，而且还用作参考支持，以比较其性能与 TNT 的性能。TNT 复合材料的 UV-Vis 光谱分析显示，Pt 负载后向可见区域的偏移大于 Pt/TiO 的光谱2. 此外，使用 Kubelka-Munk 方程和 Tauc Plot 方法，我们确定 TNT 复合材料中直接允许的转变比间接允许的转变更有可能。通过测量产氢量来评价光催化性能，实验结果表明，Pt/TNTs表现出比Pt/TiO更高的活性。2. 此外，裸 TNT 和 Pt/TNT 的 CO 生成量低于裸 TiO2和 Pt/TiO2. 因此，TNT复合材料增强了H的光催化选择性2甲酸的生成程度高于 Pt/TiO2, 因为 CO 的动力学直径 (0.38[公式: 见正文]nm) 比 CO 的大2（0.33[公式：见正文]nm）。该结果可能归因于由于直径差异，CO 无法扩散到 TNT 的孔隙中。此外，由于 Pt 和 TNT 之间的强金属-载体相互作用，XPS 结果显示 Pt 结合能的负移和 Ti 结合能的正移。因此，TNT复合材料的显着高光催化效率促进了它们作为有前途的光催化剂的应用。