Silica@layered double hydroxide core–shell hybrid materials

Abstract

A series of silica@layered double hydroxides (SiO@MgAl-CO-AMO-LDHs) have been synthesised by in situ precipitation of MgAl-CO-LDH at room temperature in the presence of amorphous spherical silica particles (∼500 nm). We have systematically investigated a number of synthetic parameters in order to evaluate their effects on the composition, morphological and physical properties of the isolated materials. Syntheses carried out at moderate stirring speeds (e.g. 500 rpm) were found to promote the formation of vertically aligned LDH platelets with respect to the silica surface. Addition rates of the metal solutions slower than 0.43 mmol h were found to create a thicker LDH shell consisting of vertically aligned LDH platelets. When the metal solutions were added rapidly (0.86 mmol h), we observed that for both slow and fast stirring speeds the synthesised core-shell materials had thin LDH shells and the majority of the LDH precipitated independent of the silica, forming unbound "free" LDH.

Synthesis of core–shell Ce-modified mixed metal oxides derived from P123-templated layered double hydroxides

“…The peaks of Ce 4p are found at the binding energies of 916.5 eV. [32][33][34] It shows that cerium exists in similar form in both materials, but the relative content of some Ce 4+ increases obviously aer calcination. More importantly, it is benecial for Ce 3+ to lose an electron to be oxidized to Ce 4+ , improving the lattice oxygen defects and the redox transformation between Ce 3+ and Ce 4+ .…”

Development of Non-Porous Silica Nanoparticles towards Cancer Photo-Theranostics

“…Silica nanoparticles fabricated from inorganic nanoparticles [ 114 , 115 , 116 , 117 , 118 , 119 , 120 , 121 ] provide attractive structures, due to the exposed inorganic nanoparticles which may facilitate magnetism and catalysis [ 118 , 119 ]. Monodisperse SiO 2 nanoparticles (230 nm) were synthesized by the Stöber method and used as the core for Fe 2 O 3 catalysts through hydrolysis precipitation.…”

A facile synthesis of layered double hydroxide based core@shell hybrid materials

“…LDHs have found practical applications in catalysts, 3 supercapacitors, 4 gas separation, 5 and drug delivery. 6 Recently, research has been directed at the synthesis of core-shell materials with LDH as the shell and silica, [7][8][9][10][11] zeolite, 12 carbon, 13,14 and metal oxides 15,16 as the core.…”