Direct Ammonia Synthesis from Air and Water Driven by Ultra-Fast Laser at Ambient Conditions

The Haber-Bosch process dominates industrial ammonia synthesis but incurs massive energy consumption and carbon emissions. Here, we demonstrate a catalyst-free approach for direct ammonia synthesis from atmospheric nitrogen and water under ambient temperature and pressure, leveraging ultra-fast laser-induced plasma at the gas-liquid interface. By optimizing irradiation parameters (irradiation time, pulse energy, number of beams) and implementing a concentric laser scanning strategy, we achieved a maximum ammonia concentration of 0.624 μmol/20mL. This method bypasses the need for high temperature/pressure or catalysts, offering a sustainable path for distributed ammonia production. Our work underscores the potential of strong optical fields in activating inert molecules like N₂ and H₂O, with implications for decarbonizing chemical synthesis.