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Hydrogen oxidation and oxygen reduction are two crucial energy conversion reactions, which are shown to be both strongly affected by the presence of intrinsically microporous polymer coatings on electrodes. Polymers of intrinsic microporosity (PIMs) are known to possess extremely high internal surface area and ability to bind gases under dry conditions. It is shown here that both, hydrogen‐ and oxygen gas binding into PIMs, also occurs under wet or “triphasic” conditions in aqueous electrolyte environments (when immersed in 0.01 M phosphate buffer at pH 7). For two known PIM materials (PIM‐1 and PIM‐PY), nanoparticles are formed by an anti‐solvent precipitation protocol and then cast as a film onto platinum or glassy carbon electrodes. Voltammetry experiments reveal evidence for hydrogen and oxygen binding. Both, PIM‐1 and PIM‐PY, locally store hydrogen or oxygen gas at the electrode surface and thereby significantly affect electrocatalytic reactivity. The onset of oxygen reduction on glassy carbon is shifted by 0.15 V in the positive direction.

Methane oxidation in water using hydrogen peroxide with a μ-nitrido iron phthalocyanine complex grafted on silica has been investigated in detail. Methyl hydroperoxide is identified as the main primary reaction product from methane oxidation. The catalyst is unstable under reaction conditions and this is discussed. However, the unmodified silica support is also found to be active for this reaction, and in particular, a Fe/SiO 2 catalyst prepared by wet impregnation is also found to be as effective as the μ-nitrido iron phthalocyanine complex grafted on silica, with higher selectivity to useful oxygenates (>80%) and displays minimal leaching or instability. A method for the reliable quantification of CO 2 in both the gas and aqueous phase is reported as this presents a key experimental difficulty in the oxidation of methane in aqueous media. © 2012 Elsevier Inc. All rights reserved.