Solar Ammonia Synthesis: Near-Complete Conversion of Intermediated Nitrogen Energy Carrier via the N₂–NO–NH₃ Route

N 2 fixation into NH 3 under ambient conditions remains greatly challenging, where a relay scheme by plasma-enabled N 2 oxidation ( p N 2 OR) and the NO reduction reaction (NORR) can be a practical route. However, the efficient conversion of NO, as the intermediate nitrogen energy carrier, has not been accomplished due to the limited mass transfer of NO in the reaction solution. Here, a tandem p N 2 OR and photocatalytic NORR route (N 2 –NO–NH 3 ) is developed to achieve sustainable NH 3 synthesis with near-complete NO conversion. The highly concentrated NO (∼1%), produced via p N 2 OR, is introduced to an absorption-photocatalysis scheme, where the efficiencies for synchronous NO dissolution and photoreduction are significantly promoted. This system delivers a near 100% NO conversion ratio and superior NH 3 selectivity (98.33% ± 0.75%) and stability (240 h) in a single-pass continuous flow. This research has successfully developed a highly profitable production route, yielding a substantial profit of $3000 per ton for NH 4 COOH as the final product.