Photochemical conversion of CO₂ into high-value C₂₊ products is difficult to achieve due to the energetic and mechanistic challenges in forming multiple C-C bonds. Herein, an efficient photocatalyst for the conversion of CO₂ into C₃H₈ is prepared by implanting Cu single atoms on Ti_0.91O₂ atomically-thin single layers. Cu single atoms promote the formation of neighbouring oxygen vacancies (V_Os) in Ti_0.91O₂ matrix. These oxygen vacancies modulate the electronic coupling interaction between Cu atoms and adjacent Ti atoms to form a unique Cu-Ti-V_O unit in Ti_0.91O₂ matrix. A high electron-based selectivity of 64.8% for C₃H₈ (product-based selectivity of 32.4%), and 86.2% for total C₂₊ hydrocarbons (product-based selectivity of 50.2%) are achieved. Theoretical calculations suggest that Cu-Ti-V_O unit may stabilize the key *CHOCO and *CH₂OCOCO intermediates and reduce their energy levels, tuning both C₁-C₁ and C₁-C₂ couplings into thermodynamically-favourable exothermal processes. Tandem catalysis mechanism and potential reaction pathway are tentatively proposed for C₃H₈ formation, involving an overall (20e⁻ – 20H⁺) reduction and coupling of three CO₂ molecules at room temperature.

由于形成多个 CC 键的能量和机械挑战，很难将CO ₂光化学转化为高价值的 C _{2+产物。在此，通过在 Ti 0.91} O ₂原子级薄的单层上注入 Cu 单原子制备了一种用于将 CO ₂转化为 C ₃ H _{8的高效光催化剂。Cu单原子促进Ti 0.91} O _{2基体中相邻氧空位(V O} s)的形成。这些氧空位调节 Cu 原子与相邻 Ti 原子之间的电子耦合相互作用，在 Ti 中形成独特的 Cu-Ti-V _O单元0.91 O ₂基质。_{C 3} H ₈的基于电子的选择性为 64.8% （基于产物的选择性为 32.4%），总 C ₂₊烃的基于电子的选择性为 86.2%（基于产物的选择性为 50.2%）。理论计算表明，Cu-Ti-V _O单元可以稳定关键的 *CHOCO 和 *CH ₂ OCOCO 中间体并降低它们的能级，将 C ₁ -C ₁和 C ₁ -C ₂耦合调整为热力学有利的放热过程。_{初步提出了C 3} H ₈的串联催化机理和潜在反应途径形成，涉及在室温下三个 CO ₂分子的整体 ( 20 e ⁻ – 20 H ⁺ ) 还原和偶联。