In Situ Diffuse Reflectance Infrared Fourier-Transform Spectroscopy Investigation of 1-Methylcyclopropene Adsorption in Cobalt-Formate Metal-Organic Framework.

Metal-organic frameworks (MOFs) find numerous applications due to their tunable adsorption/desorption properties. This work is focused on the spectroscopic investigation of the adsorption and release of ethylene (C2H4) and 1-methylcyclopropene (1-MCP)-natural plant growth hormone and its synthetic inhibitor-in the pores of Co3(HCOO)6 (Co-FA) MOF. Using in situ diffuse reflectance infrared Fourier-transform spectroscopy (DRIFTS), we have identified the molecular-level interactions between the adsorbed molecules and Co-FA pores, as evidenced by the characteristic shifts of the vibrational modes. The significant confinement of 1-MCP in Co-FA at room temperature was demonstrated, while moderate heating enabled its temperature-controlled release. In comparison, weaker but visible ethylene adsorption of C2H4 was also demonstrated, with significant desorption readily occurring at room temperature. Validation tests on bananas confirmed the superior performance of Co-FA over alternative MOFs, providing a link between molecular-level structure and practical applications.