Structural engineering and surface modification of Co MOF pores with trisodium citrate influence for enhanced triethylamine gas detection

Metal-organic frameworks (MOFs) have gained significant attention in the gas sensing field owing to their ultra-high surface area, generous active sites, and customizable porous nature. In this study, the porosity of cobalt MOFs was tuned by using trisodium citrate as a chelating agent. A systematic investigation of the structure and morphological characteristics of the cobalt MOF (Co MOF) was conducted using various characterization techniques. The results revealed that trisodium citrate treatment significantly influenced the structural and morphological properties of the Co MOF. The treated Co MOF sensor demonstrated exceptional gas sensing performance, including a maximum responsivity of 144 % at 400 ppm and 25°C, which was superior to that of the untreated Co MOF. Additionally, the sensor exhibited a faster response and recovery time (reduced from 85 seconds to 70 seconds), a lower detection limit of 4 ppm, and enhanced selectivity . The enhanced triethylamine sensing performance of the treated porous Co MOF can be attributed to its abundant surface area, oxygen vacancies , and enhanced porous dodecahedron shaped structure. Current work offers an intelligible and effective strategy for the large-scale fabrication of porous Co MOF-based gas sensors. • Co MOF is successfully synthesized by one step solution process technique. • Trisodium citrate effectively enhanced the porosity of Co MOF. • The Co MOF achieved 144 % responsivity at 400 ppm at 25°C along with faster response/recovery times (85/70 s) and lower detection limit of 4 ppm. • Exceptional stability and low detection limits, ensuring reliable long-term gas sensing performance and Offers a simple method for large-scale fabrication of Co MOF based gas sensors.