Adsorption-catalysis synergy in the visible-light-driven removal of 17β-estradiol by (Au)TiO2 nanotubes-graphene composites

• Published in: Journal of environmental chemical engineering 2024-06, Vol.12 (3), p.112885, Article 112885
• Main Authors: Cosma, Dragoş-Viorel, Roşu, Marcela-Corina, Socaci, Crina, Rostas, Arpad Mihai, Urda, Alexandra, Radu, Teodora, Turza, Alexandru, Dan, Monica, Costescu, Ruxandra, Gustavsen, Kim Robert, Dobroliubov, Oleksandr, Wang, Kaiying
• Format: Article
• Language: English
• Subjects: (Au)TiO2 nanotubes; 17β-estradiol; Adsorption; Graphene oxide; Photodegradation; Thermally reduced graphene oxide
• ISSN: 2213-3437
• DOI: 10.1016/j.jece.2024.112885

Visible light-mediated photodegradation offers a sustainable and environmentally friendly solution for removing emerging contaminants from water sources. Herein, we report on the synergy effect between adsorption and visible-light-driven photo-degradation of 17β-estradiol using (Au)TiO2 nanotubes-graphene composites. The graphene structures (graphene oxide - GO or thermally reduced graphene oxide - trGO) provide a platform for strong adsorption of 17β-estradiol molecules and facilitate the charge transfer between plasmonic Au nanoparticles and TiO2, leading to an improvement of the overall degradation process. To better understand the effect of Au nanoparticles and TiO2 separately, three different concentrations of Au (1 %, 2.5 %, and 5 %) were prepared and characterized. The estrogenic molecules preferred GO over trGO, suggesting that hydrogen bonds govern the interaction between GO and 17β-estradiol. Consequently, a higher photocatalytic efficiency of GO-containing composites was observed when removing estrogenic molecules. The role of adsorption proved crucial for capturing and retaining more contaminant molecules on the composite surface, thus increasing the odds of surface reactions with the photogenerated carriers. A total removal of 17β-estradiol has been obtained for Au (1 %, 2.5 %, and 5 %) TiO2 nanotubes-GO. The mechanism behind the adsorption and photo-degradation processes has been discussed. [Display omitted] •(Au)TiO2NT-GO/trGO nanocomposites with different metallic gold content were prepared.•The synergy between adsorption-photodegradation of 17β-estradiol was studied and discussed.•The role of adsorption proved crucial for capturing and retaining of organic molecules on nanocomposite surfaces.•A higher photocatalytic efficiency of GO-containing nanocomposites was observed.