Hui-Qin Zheng, Jun Wang, Ming-Cai Yin, Yao-Ting Fan
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引用次数: 0
Abstract
Two novel Ru(II)-phenanthroline derivatives complexes, Ru-1 and Ru-2, were synthesized and characterized. The key distinction between Ru-1 and Ru-2 lies in their ligands: L1 (2-hydroxy-5-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl) benzoic acid) and L2 (2-hydroxy-3-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)benzoic acid). In L1, the –OH group is located in the para-position, while in L2, it resides in the ortho-position. Subsequently, Pt/TiO2 and Ru-1/Pt/TiO2 (and Ru-2/Pt/TiO2) composites were prepared using photo-deposition and impregnation methods, respectively. The Ru-1/Pt/TiO2 and Ru-2/Pt/TiO2 composites were thoroughly characterized using various techniques, including ultraviolet-visible spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), fluorescence spectroscopy (FL), cyclic voltammetry (CV) experiments, and other relevant techniques. Photocatalytic hydrogen production systems were established by employing Ru-1/Pt-TiO2 and Ru-2/Pt-TiO2 as photocatalysts and ascorbic acid (H2A) as a sacrificial reagent. The results demonstrated that the maximum hydrogen production reached 1461 μmol (Ru-1/Pt/TiO2) and 843 μmol (Ru-2/Pt/TiO2) under optimized conditions with 20 mg of composite photocatalyst, 0.3 mol L–1 of H2A, and pH 4, within 4 h of irradiation (λ > 420 nm). Correspondingly, the photocatalytic hydrogen production rates were 18 267 and 10 523 μmol g–1 h–1, respectively. Mechanism studies revealed that electrons flow from the highest occupied molecular orbital (HOMO) of Ru-1 to the conduction band (CB) of TiO2, subsequently combining with H+ on the surface of the Pt metal nanoparticles to generate hydrogen gas. The holes on the lowest unoccupied molecular orbital (LUMO) of the photosensitizer are oxidized by H2A, thereby regenerating the activity of the composite catalyst by restoring the photosensitizer.
期刊介绍：
Accounts of Chemical Research presents short, concise and critical articles offering easy-to-read overviews of basic research and applications in all areas of chemistry and biochemistry. These short reviews focus on research from the author’s own laboratory and are designed to teach the reader about a research project. In addition, Accounts of Chemical Research publishes commentaries that give an informed opinion on a current research problem. Special Issues online are devoted to a single topic of unusual activity and significance.
Accounts of Chemical Research replaces the traditional article abstract with an article "Conspectus." These entries synopsize the research affording the reader a closer look at the content and significance of an article. Through this provision of a more detailed description of the article contents, the Conspectus enhances the article's discoverability by search engines and the exposure for the research.
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