The CO2 capture form concentrated CO2, flue gas and ambient air was carried out by bubbling the respective CO2 containing gas through a capture solution. Briefly, the capture solution was prepared by dissolving the amine/hydroxide in water/ethylene glycol solvent to make a concentration of 1 M. Concentrated CO2 or simulated flue gas (15% CO2, 4% O2, balance N2) was then bubbled through the solution at 30 mL min -1 for 2 h or 6 h, respectively (Figure ). For CO2 capture from air, indoor air (Reisner Lab, Yusuf Hamied Department of Chemistry, University of Cambridge) was pumped through the capture solution at a flow rate of 1.8 L min -1 after passing it through a Drierite® column for drying, using a Pawfly Ultra Quiet Air Pump (MA-60) (Figure ). Afterwards, the capture solutions were purged with N2 for 15 mins to remove any physically dissolved CO2 or O2. 0.5 mL of the solution was analysed by 1 H and C NMR spectroscopy, after addition of 1,4-dioxane (aqueous systems) or imidazole (organic systems) as internal standard and D2O (aqueous)/DMSO-d6 (organic) as the deuterated solvent to characterize and quantify the captured products. The remaining solution was used as CO2 source for the electrochemical and PEC studies after addition of supporting electrolytes/solvents as previously mentioned.