Abstract This study reveals the fabrication of a sunlight receptive flower shaped rutile TiO2 microstructure (F-TiO2) for the selective photoreduction of nitroaromatics. The crystalline F-TiO2 possesses small band gap (∼2.8 eV) and large specific surface area (193 m2g−1). Moreover, the F-TiO2 exhibited higher relaxation time (120 µs) for the electron-hole pairs due to its brilliant multi dimensional morphology that enables shorter diffusion path and multiple scattering of active sites. The experimental results revealed the superior photocatalytic activity of the F-TiO2 microstructure in contrast to active P25 and rutile TiO2 (obtained from thermally treated P25 at 800 °C for 4 h) for the reduction of nitrobenzene, m-dinitrobenzene and 2,2-dinitrobiphenyl in 50% aqueous isopropanol (hole scavenger) to aniline (42–72%), m-nitroaniline (37–42%), m-phenylenediamine (88–100%) and benzo[c]cinnoline (80–94%) respectively under UV and direct sunlight irradiation. The quantitative estimation of byproducts like acetone and hydrogen (H2) produced from iso-propanol oxidation and water splitting during instant reduction of nitroaromatics to aromatic amines is well correlated and explained on the basis of its beneficial surface structural and electronic properties.

中文翻译：

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芦荟花形金红石TiO 2 用于在阳光直射下选择性加氢硝基芳烃

摘要 本研究揭示了用于选择性光还原硝基芳烃的可接收阳光的花形金红石 TiO2 微结构 (F-TiO2) 的制备。晶体 F-TiO2 具有小带隙 (~2.8 eV) 和大比表面积 (193 m2g-1)。此外，F-TiO2 表现出更高的电子-空穴对弛豫时间（120 µs），因为它具有出色的多维形态，可实现更短的扩散路径和活性位点的多次散射。实验结果表明，与活性 P25 和金红石 TiO2（从 P25 在 800 °C 下热处理 4 小时获得）相比，F-TiO2 微结构在还原硝基苯、间二硝基苯和 2,2-二硝基联苯在 50% 异丙醇水溶液（空穴清除剂）中转化为苯胺 (42–72%)、间硝基苯胺 (37–42%)，间苯二胺（88-100%）和苯并[c]肉啉（80-94%）分别在紫外线和阳光直射下。在硝基芳烃立即还原为芳香胺的过程中，异丙醇氧化和水分解产生的副产物如丙酮和氢气 (H2) 的定量估计与相关性很好，并基于其有益的表面结构和电子特性进行了解释。