Affinity Ionic Liquids for Chemoselective Gas Sensing

Abstract

Selective gas sensing is of great importance for applications in health, safety, military, industry and environment. Many man-made and naturally occurring volatile organic compounds (VOCs) can harmfully affect human health or cause impairment to the environment. Gas analysis based on different principles has been developed to convert gaseous analytes into readable output signals. However, gas sensors such as metal-oxide semiconductors suffer from high operating temperatures that are impractical and therefore have limited its applications. The cost-effective quartz crystal microbalance (QCM) device represents an excellent platform if sensitive, selective and versatile sensing materials were available. Recent advances in affinity ionic liquids (AILs) have led them to incorporation with QCM to be highly sensitive for real-time detection of target gases at ambient temperature. The tailorable functional groups in AIL structures allow for chemoselective reaction with target analytes for single digit parts-per-billion detection on mass-sensitive QCM. This structural diversity makes AILs promising for the creation of a library of chemical sensor arrays that could be designed to efficiently detect gas mixtures simultaneously as a potential electronic in future. This review first provides brief introduction to some conventional gas sensing technologies and then delivers the latest results on our development of chemoselective AIL-on-QCM methods.

Dispersion-Free Extraction of In(III) from HCl Solutions Using a Supported Liquid Membrane Containing HA324H+Cl- Ionic Liquid as Carrier

“…Besides the above, indium is considered a hazardous element due to its carcinogenic character [14], being its removal from residual aqueous solutions i.e., resulted from a number of the above processes, is of the foremost importance, and here it is when liquid membranes must be considered as a technology suitable for the recovery of metals or other solutes present, in the few mg/L concentration order, in the wastewaters. Included in these liquid membranes operations, supported liquid membranes in their various configurations are useful for this task.…”

Reaction-Based Amine and Alcohol Gases Detection with Triazine Ionic Liquid Materials

“…The bottom ionic liquid was collected, washed with water and dichloromethane, and concentrated in vacuo to finally afford the amine ionic liquid as yellow liquid with quantitative isolated yield (1.00 g). Yellow liquid; 1 H-NMR (400 MHz, CD 3 CN) δ 2.73 (quin, J = 7.5 Hz, ImCH 2 CH 2 , 2H), 3.01 (t, J = 5.1 Hz, CH 2 NH 2 , 2H), 3.10 (t, J = 7.8 Hz, NC(CH 2 )=N, 2H), 3.56 (t, J = 5.1 Hz, OCH 2 CH 2 NH 2 , 2H), 3 Salts formed in the reaction mixture were filtered off. The solvent was removed under reduced pressure and concentrated in vacuo for 30 min.…”

“…Upon SNAr reaction of AIL 1 with a nucleophilic amine or alcohol gas, a resonance frequency drop is readily detected by a masssensitive QCM. QCM has been in constant focus of research on chemical analysis in both solutions and gas phases over the years [1][2][3]. This is due primarily to its low cost and real-time analysis of adsorption QCM has been in constant focus of research on chemical analysis in both solutions and gas phases over the years [1][2][3].…”

“…QCM has been in constant focus of research on chemical analysis in both solutions and gas phases over the years [1][2][3]. This is due primarily to its low cost and real-time analysis of adsorption QCM has been in constant focus of research on chemical analysis in both solutions and gas phases over the years [1][2][3]. This is due primarily to its low cost and real-time analysis of adsorption or recognition processes onto the surface of affinity materials such as ionic liquids deposited on electrodes when being operated at room temperature.…”

Dispersion-Free Extraction of In(III) from HCl Solutions Using a Liquid Membrane Containing HA324H⁺Cl^-Ionic Liquid

“…Thus, the recovery of this element from the above sources is an important target, and several technologies had been proposed to resolve such a situation [1], [2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], [13]. Besides the above, indium is considered a hazardous element due to its carcinogenic character [14], being its removal from residual aqueous solutions i.e., resulted from a number of the above processes, is of the foremost importance, and here it is when liquid membranes must be considered as a technology suitable for the recovery of metals or other solutes present, in the few mg/L concentration order, in the wastewaters. Included in these liquid membranes operations, supported liquid membranes in their various configurations are useful for this task.…”