Abstract

Carbon dioxide (CO2) presents one of the key chemical species and exerts significant influence on diverse environmental sub-systems. It is also an important species in the energy and industrial sector. In natural waters (oceans and rivers), a vital ionic equilibrium exists between ambient CO2 and carbonate anions (HCO3 and CO3 2-). Thus monitoring of CO2 in gas phase is a relevant and challenging. Thus the advances in the method development for CO2 detection are vital. Molecular recognition chemistry based platforms presents one such advancement by providing novel analytical tools in the form of abiotic molecules, “receptors”. Such approaches provide rapid and naked-eye based signaling. Most importantly, they are easy to use and provide a cost-effective means of analysis contrary to the bulky and traditional instrumentation based approaches. To the best of our knowledge, and for the first time, crucial molecular receptor platforms for the detection of ambient CO2 through; (i) covalent bond formation, and (ii) formation of anion activated molecular receptors has been thoroughly reviewed. Some of the crucial design considerations of molecular receptors, such as choice of fluorophore/chromophore and mechanistic aspects are momentarily discussed.