Transparent and Hydrophobic MTMS/GPTMS Hybrid Aerogel Monoliths and Coatings by Sol‐Gel Method: A Viable Remedy for Oil‐Spill Cleanup

Abstract

Sol-gel derived hybrid aerogel monoliths and coatings of methyltrimethoxysilane (MTMS) and glycidoxypropyltrimethoxysilane (GPTMS) are prepared sucessfully. MTMS/GPTMS is hydrolyzed under acidic conditions and further condensed under basic conditions to generate a gel network followed by a sequential solvent exchange process and ambient drying to obtain aerogel monoliths. The as-synthesized alcogel is homogenized in methanol and coatings are fabricated on glass substrates by dip coating method followed by controlled thermal treatment at 400 8C to get organically modified silica (ORMOSIL) based aerogel coatings. The transparent ORMOSIL aerogel coating made from the composition of MTMS/GPTMS ratio 1: 0.5 is found to be highly porous with an average pore size of~100 nm and hydrophobic coatings with water contact angle of~100 8 are obtained. The hybrid aerogel has 334 m 2 g À1 surface area (BET) with an average pore diameter of~2.7 nm, and the coating retains its hydrophobicity even after thermal treatment at 400 8C. Hybrid aerogel coatings were also made on cotton canvas fabrics which demonstrate oil adsorption-desorption properties and is a viable remedy for oilspill cleanup.

Lanthanum Phosphate-Incorporated Organosilane Nanocomposites for Gas-Phase CO2 Detection

“…The BET surface area of LaPO 4 (Table ) synthesized by the nonaqueous method after calcination at 400 °C was very low (1 m 2 g –1 ). The surface area of the ORMOSIL composition without LaPO 4 was 334 m 2 g –1 and incorporation of LaPO 4 considerably reduced the surface area of the nanocomposites (about 20%). Among the different compositions, the highest surface area was shown by the HNC–LaP-0.75 nanocomposite, which is attributed to the more uniform dispersion of the nanosized LaPO 4 in the ORMOSIL matrix as represented in the Supporting Information (Figure S5).…”

“…Thermogravimetric analysis of the ORMOSIL hybrid and the ORMOSIL–LaPO 4 hybrid nanocomposite dried at 100 °C (Supporting Information, Figure S4) has shown a three-step weight loss, with a total weight loss of ∼48% for the hybrid nanocomposite, whereas it was ∼52% for the sample without LaPO 4 . The obtained weight losses were mainly attributed to the loss of adsorbed water (50–250°C), evolution of water and methanol from the condensation reaction of residual Si–OH and Si–OMe resulting from the siloxane chain rearrangements during heating (250–350 °C), and removal of organics (300–550 °C).…”

“…The obtained weight losses were mainly attributed to the loss of adsorbed water (50–250°C), evolution of water and methanol from the condensation reaction of residual Si–OH and Si–OMe resulting from the siloxane chain rearrangements during heating (250–350 °C), and removal of organics (300–550 °C). Weight loss above 550 °C could be due to the progressive conversion of Si–CH 3 groups from an imperfect to a perfect Si–C network . From the thermogravimetric (TG) results, it is clear that heating the sample above 400 °C may drastically alter the textural and structural features of the nanocomposites, which in turn affect the functional performance.…”

Fabrication of CuO/TMSPM Coated Superhydrophobic Fabric for Self-cleaning and Oil-water Separation

“…The absorption technique based on oil capture from the water surface was applied for microscopic level separation [13,25]. In this process, modified fabric absorbed only chloroform droplets (a dense, non-aqueous liquid) on the water surface upon physical contact with the droplet (Figure 17).…”

“…Active current research on superhydrophobic (WCA ≥ 150 o and WSA ≤ 10 °)/superoleophilic surfaces may eventually have different industrial applications [21][22][23]. Such true surfaces have emerged as ideal candidates for versatile oil-water separation with high separation efficiency, and better recycling [24,25]. The discovery of superhydrophobicity and the self-cleaning property of the lotus leaves (e.g., the Lotus effect), have attracted incredible consideration due to their wide range of applications, including superhydrophobic textiles.…”