Numerous technologies are there to detect specific gases in the air. However each of these has one or more disadvantages such as sensitivity to humidity, slow detection speed, huge size and high energy cost.
To overcome these limitations, Kyoto University researchers have developed a new, low-cost material for fast and precise detection of a specific gas in various conditions. The material is reusable and it produces varying degrees of visible light associated with different gas concentrations.
The research findings explain the use of porous coordination polymer (PCP), a flexible crystalline material, which modifies according to environmental changes. The composite material, when integrated with a fluorescent reporter molecule such as distyrylbenzene (DSB), turns sensitive to CO2 gas and glows with varying intensity depending on the changing gas concentrations.
DSB is a flat and long molecule emitting blue light. When adsorbed by the PCP structure, DSB molecules twist and cause the total PCP framework to get twisted. Under this condition, the presence of CO2 makes the DSB molecules to return to its original flat and brightly glowing state and also reverses the PCP structure to its natural form. The reverting process can be done without changing the material property, thus leading to the development of various cheap, reusable gas detectors.
Source: http://www.kyoto-u.ac.jp/