Reversible oxygen-releasing from the composite of picketfence- porphyrinatocobalt and carbon in response to a 1.5 V-application

5,10,15,20-Tetrakis(α-o-pivalamidophenyl)porphyrinatocobalt(II) (CoP) complexed with N-tritylimidazole in the solid state quickly and reversibly absorbed oxygen from air (14 cm³ O₂/g), which was ascribed to a Co/dioxygen 1/1 adduct formation. The adduct formation was an exothermic reaction, and the absorbed oxygen was released above 65 °C. A disk (e.g., diameter 2 cm x 2 mm) was prepared with powders of the oxygen-absorbing, but electrically insulating, CoP complex and of electrically conductive carbon. The application of 1.5 V to the disk induced a temperature elevation in the disk, which momentarily released the absorbed oxygen. The oxygen-releasing and - absorbing cycle could be repeated more than 100 times, with a 5-min switching on-off interval under ambient conditions.