Hollow Mesoporous Silica Sphere (HMSS) as a Recyclable Nano-catalyst in an Efficient One-Pot Multicomponent Synthesis of 2-Amino-3-Cyano-4H-Pyran Derivatives

Mesoporous material has a significant role in medicine, health care, environmental monitoring, sensing the hazardous agents, and fighting against viruses and bacteria. Nano-silica sphere is an important member of the mesoporous family that noticeably flourished in biology, health care, and other industrial applications. Efficient one-pot multicomponent syntheses of 2-amino-3-cyano-4H-pyran derivatives were carried out over readily available and simply synthesized recyclable Hollow Mesoporous Silica Sphere (HMSS). Comparable yields were encountered with better efficiency, lower cost, and shorter reaction time. Hence, superior catalytic activity, flexibility, ease of recovery, tuneable hole size, and high surface to volume ratio were the major characteristics of the catalyst which distinguish this protocol from previously reported ones. The catalyst was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) techniques, and nitrogen absorption and desorption (BET) analyses. The results showed that the synthesizing of HMSS catalysts under a mild and green condition in which comparable yields were encountered with better efficiency, lower cost, and shorter reaction with other major economic advantages.

Rattle-Type Diamine-Functionalized Mesoporous Silica Sphere for Carbon Dioxide Adsorption

A rattle-type diamine-functionalized mesoporous silica sphere (DA-RMSS) was fabricated stepwise using a self-templating method through cationic surfactant assisted selective etching strategy. The rattle-type morphology of the obtained DA-RMSS material was disclosed by transmission electron microscopy, while its chemical composition was characterized by CHN elemental analysis, Fourier transform infrared spectroscopy, and solid-state 29Si cross-polarization/magic-angle-spinning nuclear magnetic resonance spectroscopic measurement, which corroborates the successful formation of siloxane network and the incorporation of organic component. Moreover, nitrogen adsorption–desorption isotherm measurement was conducted to reveal that DA-RMSS possesses large Brunauer–Emmett–Teller (BET) specific surface area of 814 m2g–1, pore volume of 0.78 cm3g–1, and narrow pore size distribution centered at 3.0 nm. Furthermore, its uptake property on carbon dioxide was also investigated in this contribution.

Trace detection of homologues and isomers based on hollow mesoporous silica sphere photonic crystals

Hollow mesoporous silica sphere photonic crystal sensors show high sensitivity and distinguishability in detecting homologues and isomers.