Cu MOF-based catalytic sensing for formaldehyde

Developing a catalyst with a uniform and well-defined crystal structure is very important to establish a catalytic sensing system with high efficiency. In this work, Cu-BTC metal–organic frameworks (MOFs) without a crystalline CuO or Cu2O phase were successfully synthesized by using a low temperature synthesis method, and the as-prepared Cu-BTC MOFs were found to have outstanding catalytic activity towards the traditional oxidase substrate, o-phenylenediamine (OPD), to generate a colored and fluorescent product. The results of the kinetics analysis revealed that the catalytic behavior of Cu-BTC MOFs towards OPD could well follow the typical Michaelis–Menten equation, indicative of a strong affinity between Cu-BTC MOFs and OPD. On the basis of these findings, taken together the condensation reaction between the –CHO group of formaldehyde and the –NH2 group of OPD to form Schiff base compounds, a novel Cu-BTC MOF-based catalytic sensing system for detecting gaseous formaldehyde could be successfully established.