Efficient Solar Driven Upgrading of N2 to Urea Through Photoredox Reactions on Pt Cluster/TiO2

Abstract Synthetic nitrogen fertilizers, such as urea, are instrumental in augmenting agricultural output and addressing the demands of a growing population. Nevertheless, conventional urea production heavily relies on energy‐intensive processes. In this study, an environmentally friendly photocatalytic method is proposed for directly and selectively synthesizing urea from nitrogen (N 2 ) and methanol (CH 3 OH using a Pt cluster‐decorated TiO 2 catalyst (Pt cluster/TiO 2 ). Remarkably, the Pt cluster/TiO 2 exhibits outstanding urea synthesis performance with a rate of 105.68 µmol g −1 h −1 and N‐selectivity of 97.29 ± 0.79%, representing the highest level of photocatalytic urea synthesis from N 2 . Further analysis with density functional theory (DFT) calculation reveals that the “ σ–π *” donor–acceptor interaction occurred between Pt clusters and N 2 , efficiently reducing the N 2 hydrogenation barrier. EPR experiments demonstrate that photogenerated electrons (e − ) and hole (h + ) are synchronously consumed through N 2 reduction and CH 3 OH oxidation, thereby accelerating urea synthesis. The crucial step of C─N coupling is initiated by the reaction between *NH─NH and *CHO intermediate, facilitated by the low energy barrier on Pt cluster/TiO 2 . This work suggests an mild route of urea production and provides profound insights into the underlying chemistry of the C─N coupling reaction, which can guide the sustainable synthesis of essential indispensable chemicals.