Immobilization of ionic liquids in translucent tin dioxide monoliths by sol–gel processing

Abstract

SnO2 translucent monolith ionogels were obtained by a sol-gel processing using bis(2-methylbutan-2-oxy)di(pentan-2,4-dionato)tin as a precursor in the presence of various ionic liquids: [BMI][Br], [BMI][TFSI], [BMI][BF4]. The confinement of ionic liquids within the gels was evidenced by Differential Scanning Calorimetry, FTIR and FT-Raman spectroscopy. The ionic liquids could be efficiently washed off, which resulted in supermicroporous solids. Calcination in air at 550 degrees C of the dried monoliths resulted in nanoporous nanocrystalline cassiterite tin dioxide particles with crystallite sizes of about 8-12 nm and mean pore sizes around 5 nm.

Use of ionic liquids in sol-gel; ionogels and applications

“…In a recent work, we explored a quite different approach, using a b-diketonato stabilized tin precursor to produce translucent monolith ionogels. A major advantage over the previous results was the possibility to use a wide range of IL ([C 4 [66].…”

Properties of Ionic Liquid Confined in Porous Silica Matrix

“…[56][57][58][59] Studies on the effect of confinement on melting point of ionic liquids has only started recently. [41][42][43] Detailed studies of silica porous matrix containing IL has been reported by Gçbel and co-workers [44] Table 2) which decreases to 8.5 8C and 8.3 8C for IL confined in silica pores of sizes 5.4 nm and 1.6 nm respectively. There is a decrease of~2 8C in m.p.…”

“…The confinement of many ILs has been found to result in changes in the thermal properties (like melting point) as studied by differential scanning calorimetry (DSC). [41][42][43] Recently, Gçbel et al [44] have studied the DSC, NMR and IR spectra obtained from inserting 4 ] etc) in silica of different pore sizes, which was achieved by varying base catalysts like pyridine, 3-fluoropyridine and 2-picoline. More recently Gçbel et al [45] obtained IL-silica monoliths of different pore sizes by functionalizing the silica pore walls by adding N,N-dimethyl-pyridine-4-yl-(3-triethoxysilylpropyl)-ammonium iodide and 3-fluoropyridine and 2-(4-pyridylethyl)triethoxysilane in TMOS in different ratios.…”

Sol-Gel Synthesis of Non-Silica Monolithic Materials

“…If the materials are dried using supercritical CO 2 (scCO 2 ), they are called aerogels. Recently ionic liquids have also been used during drying and calcination procedures, and the materials are then called ionogels [20]. …”

“…The resulting porous metal had macropores with a diameter of 600 nm [110]. Bellayer et al also utilized ionic liquids as the solvent in the sol-gel synthesis of SnO 2 monoliths [20]. Smått et al [42,104] applied the replica method to prepare manganium, cobalt and tin oxide cylindrical shape monoliths (dimensions circa 10 × 5 × 5 mm) by imbibing monolithic silica matrices with a saturated solution of the relevant inorganic salts.…”