Platinum Nanoparticle Encapsulated Metal–Organic Frameworks for Colorimetric Measurement and Facile Removal of Mercury(II)

• Published in: ACS applied materials & interfaces 2017-11, Vol.9 (46), p.40716-40725
• Main Authors: Li, Huaping, Liu, Huifang, Zhang, Jidong, Cheng, Yuxiao, Zhang, Cuiling, Fei, Xinyu, Xian, Yuezhong
• Format: Article
• Language: English
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.7b13695

Pt nanoparticle (Pt NP)@UiO-66-NH2 composites were synthesized and encompassed the benefits of permanent porosity, high thermal and chemical stability of metal–organic frameworks (MOFs), together with the functional behavior of isolated Pt NPs. The PVP-stabilized Pt NPs with the average diameter of 2.48 nm were well dispersed and confined within the framework of UiO-66-NH2. Pt NPs possess highly peroxidase-like activities and make the composites oxidize 3,3′,5,5′-tetramethylbenzidine in the presence of H2O2. Moreover, the specific interaction between Hg2+ and Pt NPs leads to the effective suppression of the peroxidase-like activity of Pt NP@UiO-66-NH2, which endows excellent selectivity for Hg2+ measurement over the interfering metal ions. Based on the colorimetric sensing system, Hg2+ is linearly measured over the range from 0 to 10 nM with a detection limit of 0.35 nM. Moreover, the as-obtained Pt NP@UiO-66-NH2 nanocomposites exhibit high capacity and good selectivity for Hg2+ adsorption, which is successfully applied to treat Hg2+ in water with removal efficiency over 99%. With these findings, Pt NP@UiO-66-NH2 composites can be used to develop a simple and rapid colorimetric sensing system and are utilized as nanoadsorbents for facile removal of Hg2+. This work not only expands the scientific researches on MOFs but also provides practical application in environmental, biological, and relative fields.