Photocatalytic conversion of CO₂ into CH₄ represents an appealing approach to alleviate the world's continued reliance on fossil fuels and global warming resulting from increasing CO₂ concentrations in the atmosphere. However, its practical application is greatly limited by serious electron–hole recombination in the photocatalysts and the production of CO and H₂ as side reactions. Herein, for the first time, it is demonstrated that the photocatalytic reduction of CO₂ to CH₄ can be significantly improved through the simultaneous alloying and hydriding of metal cocatalysts. The isolation of Cu and H atoms in Pd lattices play three roles in the enhancement of CO₂ to CH₄ conversion: 1) Cu atoms provide catalytic sites to reduce CO₂ into CO and then to CH₄ to suppress H₂ evolution; 2) H atoms improve the electron‐trapping ability of cocatalysts; and 3) H atoms accelerate the reduction of CO to CH₄, which is the rate‐limiting procedure in the conversion of CO₂ into CH₄. Arising from the synergistic interplay between Pd−H and Cu−CO sites, C₃N₄−Pd₉Cu₁H_x (15 mg) achieves 100 % selectivity for CH₄ production with an average rate of 0.018 μmol h⁻¹ under visible‐light irradiation. This work provides insights into the design of a cocatalyst for highly selective CO₂ conversion through lattice engineering at atomic precision.

中文翻译：

---

金属助催化剂的晶格工程，用于增强光催化将CO2还原为CH4

将CO ₂光催化转化为CH ₄代表了一种吸引人的方法，可以减轻世界上对大气中CO ₂浓度不断增加所导致的对化石燃料和全球变暖的持续依赖。但是，其实际应用受到光催化剂中严重的电子-空穴复合以及副反应的产生CO和H _2的极大限制。在此，首次证明通过金属助催化剂的同时合金化和氢化，可以显着改善CO ₂向CH ₄的光催化还原。Pd晶格中Cu和H原子的隔离在增强CO _2中起三个作用CH ₄转化：1）Cu原子提供催化位点，将CO ₂还原为CO，然后提供CH ₄抑制H _2的释放；2）H原子提高了助催化剂的电子俘获能力；3）H原子加速了CO向CH ₄的还原，这是CO ₂转化为CH ₄的限速过程。由于Pd-H和Cu-CO位点之间的协同相互作用，C ₃ N ₄ -Pd ₉ Cu ₁ H _x（15 mg）对CH _4的生产具有100％的选择性，平均速率为0.018μmolh ^-1在可见光照射下。这项工作提供了对通过原子精度的晶格工程进行高选择性CO ₂转化的助催化剂设计的见解。