Lv Chade, Qian Yumin, Yan Chunshuang, Ding Yu, Liu Yuanyue, Chen Gang, Yu Guihua
Materials Science and Engineering Program and Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX, 78712, USA.
MIIT Key Laboratory of Critical Materials Technology for, New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, P. R. China.
Angew Chem Int Ed Engl. 2018 Aug 6;57(32):10246-10250. doi: 10.1002/anie.201806386. Epub 2018 Jul 15.
Electrocatalytic nitrogen reduction reaction (NRR) under ambient conditions provides an intriguing picture for the conversion of N into NH . However, electrocatalytic NRR mainly relies on metal-based catalysts, and it remains a grand challenge in enabling effective N activation on metal-free catalysts. Here we report a defect engineering strategy to realize effective NRR performance (NH yield: 8.09 μg h mg , Faradaic efficiency: 11.59 %) on metal-free polymeric carbon nitride (PCN) catalyst. Illustrated by density functional theory calculations, dinitrogen molecule can be chemisorbed on as-engineered nitrogen vacancies of PCN through constructing a dinuclear end-on bound structure for spatial electron transfer. Furthermore, the N-N bond length of adsorbed N increases dramatically, which corresponds to "strong activation" system to reduce N into NH . This work also highlights the significance of defect engineering for improving electrocatalysts with weak N adsorption and activation ability.
环境条件下的电催化氮还原反应（NRR）为将N转化为NH₃提供了一个引人入胜的途径。然而，电催化NRR主要依赖于金属基催化剂，在无金属催化剂上实现有效的N活化仍然是一个巨大的挑战。在此，我们报道了一种缺陷工程策略，以在无金属的聚合氮化碳（PCN）催化剂上实现有效的NRR性能（NH₃产率：8.09 μg h⁻¹ mg⁻¹，法拉第效率：11.59%）。密度泛函理论计算表明，通过构建双核端基结合结构进行空间电子转移，二氮分子可以化学吸附在PCN经设计的氮空位上。此外，吸附的N的N-N键长度显著增加，这对应于将N还原为NH₃的“强活化”体系。这项工作还突出了缺陷工程对于改善具有弱N吸附和活化能力的电催化剂的重要性。
