Making chemicals from the air: the new frontier for hybrid electrosyntheses in artificial tree-like devices

Abstract

Making chemicals from the air is a visionary objective that can potentially revolutionise chemical production. This critical review shows that the essential elements to realise this dream exist, even the many challenges, particularly in integrating all the components and operating them in synergy. The production of (i) fertilisers and (ii) food components (carbohydrates, proteins) from the air in artificial tree-like devices is analysed, focusing on the electrosynthesis aspects. Three critical components of these devices were discussed: (i) the system to capture and concentrate small molecules (CO₂, H₂O, N₂) from the air, (ii) the electrocatalytic fixation of CO₂ and N₂, with the advances in producing directly (one-step) ammonium nitrate solution and/or urea, and (iii) the sustainable production of food from the air, via a first stage of electrocatalytic CO₂ fixation to acetate. Although there are advances in these areas, the possibility of combining them is still at an early stage. The concept of hybrid electrosyntheses technologies is crucial to realising and implementing these dream reactions. For this reason, it is indicated as the frontier research in electrosynthesis.