The inherent chemical inertness of carbon dioxide (CO 2) poses significant challenges for sensor detection capabilities. Metal-organic frameworks (MOFs) exhibit high porosity and surface area, making them highly promising for gas adsorption. Numerous studies have explored the use of MOFs for CO 2 adsorption, detection, catalysis, and storage. However, this approach presents significant challenges. To unlock this porosity, MOFs are typically fully activated by removing all adsorbed guests using high temperatures and low pressures. This is energy-intensive and impractical if the MOFs are part of a composite material whose maximum temperature is below the MOFs' activation temperature. The adsorption behavior of Mg-MOF-74 toward CO 2 under different conditions was investigated to explore the effect of activation temperature on adsorption. Adsorption experiments yielded anomalous results: partially activated samples adsorbed 20% more CO 2 per unit of framework material than fully activated samples. The kinetics and thermodynamics of the adsorption process were analyzed using the Langmuir adsorption model and the Clausius-Clapeyron equation, confirming that the interaction between CO 2's quadrupole moment and the electric field generated by water molecules enhances CO 2 absorption. As a proof-of-concept, reversible CO 2 detection at room temperature was achieved by combining the gravimetric sensing capability of a quartz crystal microbalance (QCM) with Mg-MOF-74 under various conditions. These findings could open new possibilities for tuning the adsorption behavior of MOFs for CO 2 capture and other applications.