Synergy of Oxygen Vacancies and Ni Single Atoms toward Efficient Urea Photosynthesis from CO2 and N2

The direct photochemical synthesis of urea under mild conditions presents considerable promise. Nevertheless, the photocatalytic urea synthesis is severely restricted by the co‐adsorption and activation of inert CO2 and N2 molecules. Herein, an ingenious design of a high‐performance Ni1/TiO2‐X catalyst by strategically coupling Ni single atoms and oxygen vacancies (Ov) onto urchin‐like TiO2 architecture. By virtue of the unique synergistic catalysis between atomically dispersed Ni species and precisely engineered Ov sites, the Ni1/TiO2‐X catalyst achieves a remarkable urea production rate of 15.73 µmol/gcat./h. Further mechanistic studies reveal that the atomically dispersed Ni sites facilitate N2 adsorption and activation, generating *N2 species, while the adjacent Ov sites activate CO2 to form *CO intermediates. More intriguingly, the *CO species can migrate from the Ov site to the nearby Ni active centers, where they spontaneously undergo thermodynamic coupling with *N2 to form a “tower‐like” urea precursor (*NCON* intermediate), subsequently converting to urea. The present work establishes a dual‐active‐site mechanism, comprising isolated Ni centers and adjacent Ov sites, which synergistically lowers the activation barrier for urea photosynthesis and accelerates reaction kinetics, and pioneers a transition strategy for the environmentally friendly and efficient synthesis of high‐value products.