Selective electrochemical reduction of essential small molecules (CO₂, N₂, NO_x) into energy-dense compounds is a promising strategy for recycling these and exploring their use carbon and nitrogen source. However, efficient and selective earth abundant metal catalysts for these challenging reactions remain scarce. We will present here an array of strategies inspired from biological systems to promote these reactions with high selectivity and efficiency. The importance of tackling these challenging reaction at multiple scale will be illustrated by a series of molecular and heterogeneous catalysts replicating enzymatic features, from their active sites including secondary features such as hydrophilic and hydrophobic domains to the overall shape of organs involved in gas trapping.