Green One-Pot Synthesis of Silver Nanoparticles/Metal–Organic Gels Hybrid and Its Promising SERS Application

Recently, metal–organic gels (MOGs) appear as a potential alternative to the well-known metal–organic frameworks due to the easier and more straightforward shaping and other unique features. However, the modification of MOGs with noble metal nanoparticles is still in its infancy. On the other hand, developing multifunctional SERS substrate materials with a facile way still remains a great challenge. Herein, silver nanoparticles/metal–organic gels (AgNPs/MOGs) hybrid, a novel dual functional SERS-active platform that is both Raman signal molecule and highly sensitive SERS substrate, was fabricated by a one-pot approach for the first time. The AgNPs/MOGs hybrid, which was obtained by simply mixing 4-(2,2′:6′,2″-terpyridine)-4′-ylbenzoic acid (Hcptpy) and silver ion (Ag + ), followed by heating without adding extra reducing reagent, exhibited an outstanding Raman signal due to the combination of the Raman label source of Hcptpy and the localized surface plasmon resonance properties of AgNPs, endowing it an excellent SERS platform for permanganate sensing. It is worth noting that Hcptpy plays dual roles of coordination and reduction in the synthesis of the hybrid, namely, as a coordinating agent to coordinate with Ag + to form MOGs and as a reducing agent to in situ reduce Ag + to form AgNPs. These results foresee that this one-pot synthesis of noble metal nanoparticles modified MOGs hybrids is a promising strategy toward the facile and high-yield production of novel binary functional SERS platforms.