Synthesis and characterization of functionalized mesoporous silica nanoparticles for sensing applications

Abstract

Porosity in materials stretches out from the nanoscale up to the macro scale and is a highly researched area particularly due to the reason that the design outline may be directed by control of solution chemistry in the crystallization of complex structures. In 1992, Mobil Research and Development Corporation paved a new road in the field of mesoporous silica materials. The fabrication of Mobil Crystalline of Material (MCM) series was a major development and these materials provide endless possibilities for applications in areas such as catalysis, separation, sensing and biomedical fields. This team of researchers synthesized various MCM-41 sieves with pore size ranging from ~15and#506; to ~100and#506;. Mesoporous silica nanoparticles (MSNs) carefully synthesized, possess unique properties like large pore volume with tunable pore size, high surface area and high loading capacity making them excellent candidates for sensing applications. The mesoporous silica may belong to any of the families: MCM-41, SBA-15 or KIT-6, each one of them is characterized with unique morphology leading to different applications. In the present work, mesoporous silica nanoparticles MCM-41 with large surface area ranging between 400-800 m2 /g, pore volume of the order of 0.12-0.78 cm3 /g and ordered pore arrangements have been successfully synthesized and comprehensibly characterized. The sol gel method has yielded mesoporous silica with desired properties. The formation mechanism of the synthesized mesoporous silica nanoparticles MCM-41 is explained by liquid crystal templating. The mesoporous silica MCM-41 was further doped with different metal ions and the doped mesoporous silica nanoparticles were studied for humidity sensing characteristics. Humidity present in the atmosphere has a significant effect on our lives. At the same time control of humidity is needed to attain optimum humidity levels in facilities like food processing industry, medical and biological storage units, electronics, libraries and museums to name a few. This is where lies th