In situ growth of conductive bimetallic catecholate MOFs on porous graphene for high-performance formaldehyde gas sensing.

High-performance chemoresistive gas sensors capable of rapidly detecting and identifying formaldehyde, a probable carcinogenic volatile organic compound (VOC), are essential for numerous applications, especially for monitoring indoor air quality. Conventional materials used for formaldehyde sensors face significant challenges, including long response times, poor stability, and limited selectivity. To overcome these challenges, this study proposes novel chemoresistive sensors combining bimetallic conductive catecholate (Ni-CuCAT) MOFs with laser-scribed graphene (LSG) porous structures. Experimental results demonstrate outstanding sensor performance for formaldehyde detection, showcasing ultrafast response times (1-2 seconds), a low detection limit (0.5 ppm), and exceptional stability, all achieved at room temperature (20 °C). Furthermore, the use of LSG as a substrate for Ni-CuCAT growth enables flexibility and advanced patterning strategies, addressing key limitations in MOF-based electronic devices. These findings provide crucial insights into the potential application of MOFtronics in high-performance healthcare devices.