Abstract
Functional mesoporous silica probes, MCM-TFM and SBA-TFM, have been synthesized with varying pore sizes and having S-donor sites judiciously selected to bind soft metal centers. The soft S-donor centers are contributed by the thiol functional groups that are introduced into the silica matrices by functionalization with tris(4-formylphenyl)amine followed by 2-aminothiophenol. The materials rapidly and selectively detect Hg2+ colorimetrically and the change in color profile can be perceived through bare eyes. The probes can decontaminate the pollutant heavy metal from aqueous medium at ppb level and the materials are recyclable and reusable for several separation cycles.
Highlights
Mercury is a bio-accumulative, prevalent pollutant heavy metal which is found in air, water and soil[1]
In order to address the aforementioned challenges, in this contribution we report mesoporous silica, MCM-41 and SBA-15, based functionalized probes with S and N donor sites, MCM-TFM and SBA-TFM (Fig. 1), which can selectively sense as well as scavenge Hg2+ ions from aqueous medium through covalent interaction with very high efficiency
The materials have S-donor sites anchored on their surface which can selectively detect and sense Hg2+ among soft centres like As3+, Cd2+ and Pb2+ and other relevant metal ions
Summary
Mercury is a bio-accumulative, prevalent pollutant heavy metal which is found in air, water and soil[1]. Common adsorbents like activated carbons[10], zeolites[11] and clays[12] generally have low capacity and bind weakly to the heavy metal ion and thio-functionalized materials are more effective for Hg2+ removal due to soft-soft interactions[13,14]. The existing adsorbents suffer from drawbacks like poor surface area and inhomogeneous distribution of binding sites which affect the efficiency of the removal process In this respect, mesoporous silica based structures have drawn considerable interest as they can simultaneously detect as well as separate the metal ions[17,18,19] by virtue of the organic functional groups homogeneously anchored on their surface and large surface area with uniform pore size distribution. The thiol functionalized probes that have been prepared here show enhanced selective chromogenic behaviour toward Hg2+ ions and the colour change from pale yellow to dark orange is visible to the naked eyes
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
