Sluggish charge separation dynamics resulting from the amorphous structure and the lack of driving force for graphitic carbon nitride (GCN) limits its highly effective CO₂ photoreduction performance. Herein, a built-in electric field (BEF) was constructed for a well-designed CCN/Ni hybrid composed of crystalline carbon nitride (CCN) and a metal complex, 2,2′-bipyridine-4,4′-dicarboxylic acid NiBr₂ (dcabpyNiBr₂), to steer charge carrier separation and migration. The CCN/Ni hybrid was synthesized via a solution–dispersion and molten-salt two-step approach, displaying an improved CO₂ photoreduction to CO rate of 8.64 μmol g⁻¹ h⁻¹. In situ experimental results and theoretical simulations further investigated the relationships between BEF and photocatalytic activity. This work demonstrates an effective strategy to obtain high-efficiency photocatalytic systems by engineering the crystal structure and constructing a BEF.

中文翻译：

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构建具有内置电场的镍络合物/结晶氮化碳杂化物，用于促进 CO2 光还原


非晶结构导致的电荷分离动力学缓慢，并且石墨氮化碳 （GCN） 缺乏驱动力，限制了其高效的 CO₂ 光还原性能。在此，为由结晶氮化碳 （CCN） 和金属络合物 2,2′-联吡啶-4,4′-二羧酸 NiBr₂ （dcabpyNiBr₂） 组成的精心设计的 CCN/Ni 杂化物构建了一个内置电场 （BEF），以控制电荷载流子分离和迁移。CCN/Ni 杂化物是通过溶液-分散和熔融盐两步法合成的，显示出改进的 CO₂ 光还原到 8.64 μmol ^{g-1 h-1} 的 CO 速率。原位实验结果和理论模拟进一步研究了 BEF 与光催化活性之间的关系。这项工作展示了一种通过设计晶体结构和构建 BEF 来获得高效光催化系统的有效策略。