Fu Bing, Wu Zhijiao, Cao Shuang, Guo Kai, Piao Lingyu
CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China.
Nanoscale. 2020 Feb 27;12(8):4895-4902. doi: 10.1039/c9nr10870j.
The spatial separation of reduction and oxidation reaction sites on the different facets of a semiconductor is an ideal and promising route for overall photocatalytic water splitting due to efficient charge carrier separation. Rutile TiO2 has separate oxidation and reduction crystal facets and can be used to achieve direct splitting of pure water under ultraviolet (UV) light irradiation. In order to improve the rate of water oxidation reaction, the ratio of different crystal facets of rutile should be regulated controllably. However, the preparation of rutile TiO2 architecture has been limited by the availability of synthetic techniques. In this study, rutile TiO2 nanorods with various aspect ratios were accurately prepared in the presence of Cl- anions and H+ cations, which were found to play a crucial role in forming the morphology of rutile TiO2 nanorods. In addition, the mechanism involving the growth of rutile TiO2 nanorods with different aspect ratios is proposed. Rutile TiO2 nanorods with a high proportion of oxidative (111) facets provided higher overall water splitting reactivity.
由于能实现高效的电荷载流子分离，半导体不同晶面上还原和氧化反应位点的空间分离是实现整体光催化水分解的理想且有前景的途径。金红石型TiO₂具有独立的氧化和还原晶面，可用于在紫外光照射下实现纯水的直接分解。为了提高水氧化反应的速率，应可控地调节金红石型不同晶面的比例。然而，金红石型TiO₂结构的制备受到合成技术可用性的限制。在本研究中，在Cl⁻阴离子和H⁺阳离子存在的情况下精确制备了具有不同纵横比的金红石型TiO₂纳米棒，发现它们在形成金红石型TiO₂纳米棒的形态方面起着关键作用。此外，还提出了涉及不同纵横比的金红石型TiO₂纳米棒生长的机制。具有高比例氧化（111）面的金红石型TiO₂纳米棒具有更高的整体水分解反应活性。
