The issue of gas solubility has profound implications for studying the activity of oxygen reduction reaction electrocatalysts. Aqueous solutions endowed with permanent microporosity — termed microporous water — could be the answer.
Why does the food industry tend to use carbon dioxide rather than any other gas in sparkling drinks? It’s partially a solubility issue; non-polar gases are only sparingly soluble in water. For oxygen in water1, it’s a matter of entropy as, although the dissolution process is exothermic, the entropic term is relatively large and negative (–130 J K–1 mol–1). In pure water, oxygen solubility is of the order of 1.3 mM (298 K, 1 atm), and the value for nitrogen and other related small molecules is similar. In contrast, the quadrupolar