3 years ago

Supported gold clusters as effective and reusable photocatalysts for the abatement of endocrine-disrupting chemicals under visible light

Supported gold clusters as effective and reusable photocatalysts for the abatement of endocrine-disrupting chemicals under visible light
Photocatalysts based on glutathione-protected Au clusters (1.5±0.4nm) were synthesized and assessed for the visible-light degradation of ten different endocrine-disrupting chemicals (EDCs) and related compounds. In its as-prepared form, the Au clusters undergo rapid photocharge recombination resulting in no appreciable photocatalytic activity. Coupling with non-activated TiO2 acceptor was necessary to achieve efficient interfacial charge separation that allowed the photocharges on the Au clusters to be effectively harvested for surface redox reactions. Under visible light excitation, the Au cluster undergoes ligand-to-metal charge transfer and resulting in the accumulation of photohole on the glutathione ligand (i.e., the HOMO state). The transfer of photoholes to the hydrogen-bonded EDCs is identified as the main oxidation pathway. The hole transfer oxidation, which was probably complemented by superoxide radicals attack, was necessary since the low HOMO level of the Au clusters (+1.21V vs. RHE, pH 0) disallowed the production of hydroxyl radicals (+2.68V vs. RHE, pH 0). As such, the photocatalytic degradation rates of EDCs are in accordance with the trend of Langmuir adsorption capacities. Lastly, we demonstrated the high reusability of the Au cluster/TiO2 photocatalyst, retaining 96% of the initial activity even after 5 repeated cycles or equivalent to 25h of continuous irradiation.

Publisher URL: www.sciencedirect.com/science

DOI: S0021951717302798

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.