Green and large-scale production of ammonia: Laser-driven pyrolysis of nitrogen-enriched biomass

As a vital chemical, ammonia (NH3) plays an irreplaceable role in many fields such as chemical synthesis and energy storage. Green renewable biomass can be converted into biofuels, but its nitrogen resources are underused throughout. Laser-driven pyrolysis is envisaged to debuts as a bridge to connect them to realize the direct conversion from nitrogen-rich biomass into ammonia. The pulsed laser-induced local-transient thermal effect recognized the biological nitrogen resources conversion, such as cheap and plentiful yeasts, to small gaseous molecules and achieved spectacular ammonia production rate up to 260.4 mg/h, an order of magnitude higher performance than thermochemical ammonia synthesis. Simultaneously, the tiny hot point generated by a low-energy laser (20 W) guarantees the whole ammonia synthesis reaction system is in a mild environment of low temperature and normal pressure. Additionally, the remaining solid residue after laser-driven pyrolysis also can be further exploited as a highly active catalyst for electrocatalytic nitrate reduction reaction (NIRR).