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Solar‐driven CO2 conversion is a promising approach to tackle the issues of increasing greenhouse gases and energy shortage. Herein, a defective amine/silver species‐modified mesoporous TiO2 (NH2–TiO2−x–Ag) nanoparticle assembly for photocatalytic CO2 reduction is reported. In particular, simultaneous oxygen vacancy incorporation and silver species anchoring in the formation of NH2–TiO2 derived from amine‐modified protonated titanate during polyol‐mediated solvothermal treatment are achieved. Indeed, the NH2–TiO2−x–Ag with different amounts of Ag species can enhance photocatalytic CO2 reduction into CH4 and CO. The NH2–TiO2−x–Ag‐0.05 sample has the highest CH4 and CO yields with rates of 6.11 and 0.91 μmol g−1 h−1, respectively, which are about 10.7 and 7 times higher than that of pristine NH2–TiO2. These findings demonstrate that the synergic impact of oxygen vacancies and metallic silver sites embedded into NH2–TiO2 can prevent poor light harvesting, fast recombination of photogenerated electrons and holes, and inadequate surface‐active sites.

Photocatalytic CO2 reduction is a promising technology for reaching the aim of “ carbon peaking and carbon neutrality”, and it is crucial to design efficient photocatalysts with a rational surface and interface tailoring. Considering that amine modification on the surface of the photocatalyst could offer a favorable impact on the adsorption and activation of CO2, in this work, amine-modified brookite TiO2 nanorods (NH2-B-TiO2) coupled with CuxS (NH2-B-TiO2-CuxS) were effectively fabricated via a facile refluxing method. The formation of a p–n junction at the interface between the NH2-B-TiO2 and the CuxS could facilitate the separation and transfer of photogenerated carriers. Consequently, under light irradiation for 4 h, when the CuxS content is 16%, the maximum performance for conversion of CO2 to CH4 reaches at a rate of 3.34 μmol g−1 h−1 in the NH2-B-TiO2-CuxS composite, which is approximately 4 times greater than that of pure NH2-B-TiO2. It is hoped that this work could deliver an approach to construct an amine-enriched p–n junction for efficient CO2 photoreduction.

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