Reactivity of Bioinspired Magnesium-Organic Networks under CO₂ and O₂ Exposure

Photosynthesis is the model system for energy conversion. It uses CO₂ as a starting reactant to convert solar energy into chemical energy, i.e., organic molecules or biomass. The first and rate-determining step of this cycle is the immobilization and activation of CO₂, catalyzed by RuBisCO enzyme, the most abundant protein on earth. Here, we propose a strategy to develop novel biomimetic two-dimensional (2D) nanostructures for CO₂ adsorption at room temperature by reductionist mimicking of the Mg-carboxylate RuBisCO active site. We present a method to synthesize a 2D surface-supported system based on Mg²⁺ centers stabilized by a carboxylate environment and track their structural dynamics and reactivity under either CO₂ or O₂ exposure at room temperature. The CO₂ molecules adsorb temporarily on the Mg²⁺ centers, producing a charge imbalance that catalyzes a phase transition into a different configuration, whereas O₂ adsorbs on the Mg²⁺ center, giving rise to a distortion in the metal-organic bonds that eventually leads to the collapse of the structure. The combination of bioinspired synthesis and surface reactivity studies demonstrated here for Mg-based 2D ionic networks holds promise for the development of new catalysts that can work at room temperature.