Metal–Organic Frameworks and Their Composites for Sensing Applications

Metal–organic frameworks (MOFs) are microporous novel coordination polymers with extraordinary structural geometry of metal centers or nodes associated with ligands. Different organic molecules such as benzene 1,4-dicarboxylic acid, biphenyl-4,4'-dicarboxylic acid, benzene 1,3,5-tricarboxylic acid, and azoles are commonly used as bridging ligands in MOFs. MOFs possess significant pore parameters with the ability to functionalize different chemical compounds to enrich their widespread research attention in the field of electrochromic, catalytic, storage, sequestration, and sensing applications. Functionalized MOFs are promising nanomaterials to probe sensing devices for the detection of toxic gases such as H2S, NH3, and CO2 and biomolecules like protein, enzymes, and antibodies with high selectivity as well as sensitivity. Luminescent MOFs are promising candidates for optical sensing applications. In this chapter, the sensing performance of MOFs and their composite nanostructures have been discussed including electrochemical sensing, gas sensing, optical sensing, and biosensing applications for the detection of different hazardous gases, solvent molecules as well as biomolecules.