Enhanced catalytic activity and near room temperature gas sensing properties of SnO₂nanoclusters@mesoporous Sn(iv) organophosphonate composite

Abstract

A simple, facile and one-pot route for preparing SnO nanoclusters embedded on a mesoporous Sn(iv) organophosphonate (MSnP) framework is described. Reaction of SnCl·5HO with a flexible tris-phosphonic acid, mesityl-1,3,5-tris(methylenephosphonic acid), in the presence of a surfactant under hydrothermal conditions produced the desired nanocomposite, SnO@MSnP. Analytical, spectroscopic and microscopic studies establish that SnO@MSnP composite is comprised of SnO nanoparticles of an average size of 5 nm evenly and abundantly dispersed over the MSnP framework. The mesoporous metal organophosphonate support significantly augments the catalytic efficacy and vapor sensitivity of SnO nanoparticles. The catalytic efficiency of SnO@MSnP was tested for two acid-catalyzed reactions: deoximation reaction and esterification of fatty acids. SnO@MSnP exhibits remarkable sensitivity towards ammonia and acetone vapors at near room temperature and under open atmospheric conditions. The present method represents an important step towards preparation of mesoporous metal organophosphonate supported metal oxide nanoclusters and hence offers easy access to functional metal oxide based nanocomposites.

A Simple Route to Prepare Polypyrrole-Coated Filter Papers via Vapor Phase Polymerization and Their Gas Sensing Application

“…The repeatability of the sensors can also be observed by plotting % response of the respective sensors with time. To perform this experiment, a two-necked conical flask was used where the sensor was mounted, and the liquid ammonia inserted was vaporized continuously by using a constant 50 °C temperature inside the conical flask with the help of a hot plate as reported elsewhere . The sensing response was calculated by using eq where R a and R g are resistances of the material in air and in the presence of the analyte, respectively.…”

“…To perform this experiment, a two-necked conical flask was used where the sensor was mounted, and the liquid ammonia inserted was vaporized continuously by using a constant 50 °C temperature inside the conical flask with the help of a hot plate as reported elsewhere. 54 The sensing response was calculated by using eq 4…”

Sustainable and Efficient Route for the Regeneration of Carbonyl Compounds from Oximes Using Aqueous Extract of Sapindus laurifolia under Microwave Radiation

“…Some of the well-known deoximating agents are N 2 O 4 , pyridinium chlorochromate (PCC), tert -butyl hydroperoxide (TBHP), KMnO 4 /alumina, (PhSeO) 2 O, TMSCl/NaNO 2 , Raney nickel, sodium perborate/HOAc, NaHSO 3 , etc., and several transition-metal salts involve Tl­(NO 3 ) 3 , Cr­(OAc) 2 , Mn­(OAc) 3 , trimethylsilyl chlorochromate, BiBr 3 /Bi­(OTf) 3 , 2-nitro-4,5-dichloropyridazin-3­(2 H )-one, and Al­(NO 3 ) 3 ·9H 2 O in the presence of catalytic amounts of NaBr in CH 2 Cl 2 at room temperature . Furthermore, tetraethyl ammonium chlorochromate (TEACC) in dimethylsulfoxide, potassium permanganate–graphite, citric acid, and many other reagents − have recently been reported as deoximating agents. However, most of these reagents are toxic, corrosive, and expensive and take a longer reaction time for completion.…”

Tin/Tin Oxide Nanostructures: Formation, Application, and Atomic and Electronic Structure Peculiarities

“…Furthermore, the selectivity and sensitivity of such sensors can be easily adjusted by make different nanostructured SnO 2 [20,[150][151][152]. For example, SnO 2 nanoclusters embedded on a mesoporous Sn organophosphonate framework was found to be an efficient approach to enable gas sensors to have remarkable sensitivity toward ammonia and acetone [153]. SnO 2 nanowires synthesized by the CVD process were also reported to have high sensitivity toward different gases, such as H 2 S [154], NO 2 [155,156], and water vapor [157].…”