Fabrication of a Reusable Carbon Dot/Gold Nanoparticle/Metal–Organic Framework Film for Fluorescence Detection of Lead Ions in Water

• Published in: ACS applied materials & interfaces Vol. 14; no. 31; pp. 35755 - 35768
• Main Authors: Olorunyomi, Joseph F., White, Jacinta F., Gengenbach, Thomas R., Caruso, Rachel A., Doherty, Cara M.
• Format: Journal Article
• Language: English
• Published: American Chemical Society 10-08-2022
• Subjects: Energy, Environmental, and Catalysis Applications; carbon dots; chemical sensing; gold nanoparticles; fluorescence; metal−organic frameworks
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.2c09122

Solid-state sensing platforms are desirable for the development of reusable sensors to promote public health measures such as testing for drinking water contamination. A bioinspired metal–organic framework (MOF)-based material has been developed by imitating metal–protein interactions in biological systems to attain high sensitivity and selectivity to Pb2+ through fluorescence sensing. A zirconium terephthalate-type framework (also known as NH2-UiO-66) was modified with both gold nanoparticles and thiol-functionalized carbon dots to give HS-C/Au­(x)/UiO-66 composites with different Au content (x) and were subsequently adapted into films that show extraordinary sensitivity to Pb2+. The HS-C/Au(1.4)/UiO-66 film that consists of 1.4 wt % Au shows a quenching response with the limit of detection of 80 parts per trillion and sustained performance for five cycles. Moreover, the fluorescence response of the HS-C/Au­(x)/UiO-66 film to Pb2+ can be reversed from emission quenching to enrichment of fluorescence by increasing the Au content. The performance of the HS-C/Au­(x)/UiO-66 film as a solid-state sensor demonstrates its potential for application in reusable sensing devices to ensure public safety from Pb2+ contamination in drinking water.