(Invited) Electrochemical Detection of Gases and Explosives in Ionic Liquids in Different Humidity Environments

摘要

Amperometric gas sensors (AGSs) are widely used due to their many advantages, such as low-cost, portability, durability, wide linear range, high sensitivity and high selectivity. They are available commercially from a number of companies, and can detect a range of redox-active gases. The sensor devices typically employ a water/sulfuric acid mixture as the electrolyte in contact with three electrodes, covered by a gas-permeable membrane. Room temperature ionic liquids (RTILs) have strong potential for use as alternative 'designer solvents' in membrane-free AGSs, which would solve the existing technological problems of commercial AGSs, including the slow diffusion through the membrane and solvent evaporation. Their non-volatility would enable the membrane to be dispensed with, and the entire sensor to be miniaturised to provide optimal functionality over a much wider range of ambient conditions and with a longer lifespan. This allows and encourages innovative designs, with the potential for gas sensors to move from single, finite devices to more sophisticated systems that exploit recent advances in portable electronics and computing.