Abstract

A hybrid organic–inorganic catalyst of polyheptazine and TiO₂ nanotubes was obtained by polymerization of polyheptazine directly on the surface of layered titanate nanotubes (TiNT) at 400 °C; leading to a phase transition from TiNT to TiO₂ anatase. This method induces the polymerization in-between the layers of TiNTs, in contrast to what happens on commercial TiO₂ nanoparticles (P25), for which polymer adsorption occurs only onto the outer surface. As a result, the hybrid materials exhibit enhanced physical–chemical properties, resulting in improved photocatalytic response; the methylene blue degradation was 1.28-times higher using the hybrid polyheptazine-TiO₂ nanotubes as a photocatalyst, in comparison to the use of polyheptazine-P25. Besides, polyheptazine-TiO₂ nanotubes show higher photo-electrocatalytic activity than TiNTs, whereas polyheptazine-P25 exhibits lower activity than P25. The lower band-gap energies, zeta potentials and higher surface area make the polyheptazine-TiO₂ nanotubes more efficient photocatalysts under visible light in comparison to P25-based nanoparticles.

Graphic abstract

中文翻译：

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在钛酸酯纳米管的层间空间中聚庚嗪的直接聚合可增强可见光响应

摘要

通过在400°C的温度下直接在层状钛酸酯纳米管（TiNT）上聚合聚庚嗪，得到聚庚嗪和TiO ₂纳米管的有机-无机杂化催化剂。导致从TiNT到TiO ₂锐钛矿的相变。与在商用TiO ₂纳米颗粒（P25）上发生的情况相反，该方法仅在外表面吸附聚合物，因此该方法在TiNTs层之间引发聚合。结果，杂化材料表现出增强的物理化学性能，从而改善了光催化反应。杂多嗪-TiO ₂杂化后，亚甲基蓝的降解速率提高了1.28倍与使用聚庚嗪-P25相比，纳米管作为光催化剂。此外，聚庚嗪-TiO ₂纳米管显示出比TiNTs高的光电催化活性，而聚庚嗪-P25显示出比P25更低的活性。与基于P25的纳米粒子相比，较低的带隙能，ζ电位和较高的表面积使聚庚嗪-TiO ₂纳米管在可见光下更有效。

图形摘要