Material stability (thermal, chemical or mechanical) and recyclability (#3) are crucial in reducing the economic and environmental impact of the DAC unit. Using materials which are not stable or reusable for many capture and release cycles may increase operational costs for material replacement, and a higher environmental impact, due to a greater demand for material synthesis, disposal and, in some cases, degradation due to oxidation or thermal decomposition. For most materials there are questions on stability when operating in a real-world environment, especially as a result of exposure to high oxygen concentrations or other impurities in air. The degradation of materials may also lead to atmospheric release of unwanted compounds which could require additional remediation cost. 115,116 However, there is currently a lack of studies on the mechanisms that cause material aging, degradation, and loss to the atmosphere. Also, it has been shown that different environments have a varying effect on materials performance, especially productivity (#3).