The mesoporous solid acid–base Cs–B–Zr mixed oxides were synthesized using the co-precipitation method followed by a subsequent thermal treatment. The catalytic activity of solid Cs–B–Zr mixed oxide was tested for solvent free acid–base catalysed direct alkylolamines with alcohols as green alkylating agent. The effects of Cs/B/Zr ratio, calcination temperature, reaction conditions, and reaction substrate on the catalytic performance of the catalysts were investigated. The XRD, N2 adsorption–desorption, ICP-OES, FT-IR and NH3/CO2-TPD results showed that the mesoporous structure and acid–base properties of the catalysts play important roles in the reaction. A suitable number of acid and basic sites on the catalyst lead to a high activity for the N-alkylation reaction.

We herein designed a ratiometric fluorescent probe by hybridizing fluorescein isothiocyanate-doped silica nanoparticles with CdTe/CdS quantum dots and demonstrated its efficiency for visual detection of Hg2+. The color of the solution gradually turned from red to green along with the increase of Hg2+ concentration.

We report a facile route using precipitation reaction and sequential calcination to synthesize three-dimensional (3D) flower-like magnesium borate (Mg3B2O6) nanoarchitectures with poly(vinyl pyrrolidone) (PVP) as the template. The structure and morphology were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM). The results indicate that 3D flower-like Mg3B2O6 microspheres with diameters of 0.6–1.0 μm are composed of large numbers of single crystalline nanosheets with thickness of about 10 nm. The N2 sorption result and pore-size distribution analysis show that mesopores and macropores exist in the 3D flower-like nanostructures. The mesopores and macropores will endow the hierarchical microspheres with novel application potentials.3D flower-like Mg3B2O6 microspheres assembled by nanosheets were synthesized via PVP-assisted method. Mesopores and macropores exist in the 3D flower-like Mg3B2O6 microspheres.Highlights► 3D flower-like Mg3B2O6 microspheres have been obtained via PVP-assisted method. ► The diameters of the Mg3B2O6 microspheres are 0.6–1.0 μm. ► The Mg3B2O6 microspheres are composed of single crystalline nanosheets. ► Mesopores and macropores exist in the 3D flower-like Mg3B2O6 microspheres.