Key Lab for Anisotropy and Texture of Materials, School of Materials Science and Engineering, Northeastern University, Shenyang 110819, China.
Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, Sendai 980-8577, Japan.
Phys Chem Chem Phys. 2023 May 10;25(18):13126-13135. doi: 10.1039/d2cp05959b.
The electrocatalytic nitrogen reduction reaction (ENRR) has been regarded as an eco-friendly and feasible substitute for the Haber-Bosch method. Identifying the effective catalysts for the ENRR is an extremely important prerequisite but challenging. Herein, asymmetrical silicon-metal dimer catalysts doped into g-CN nanosheets with nitrogen vacancies (SiM@CN) were designed to address nitrogen activation and reduction. The concept catalysts of SiM@CN can combine the advantages of silicon-based and metal-based catalysts during the ENRR. Among the catalysts investigated, SiMo@CN and SiRu@CN exhibited the highest activities towards the ENRR with ultra-low onset potentials of -0.20 and -0.39 V; meanwhile, they suppressed the competing hydrogen evolution reaction (HER) due to the relative difficulty in releasing hydrogen. Additionally, SiRu@CN is demonstrated to possess strong hydrophobicity, which is greatly beneficial to the production of ammonia. This research provides insights into asymmetrical silicon-metal dimer catalysts and reveals a new method for developing dual-atom electrocatalysts. This asymmetrical dimer strategy can be applied in other electrocatalytic reactions for energy conversion.
电催化氮气还原反应（ENRR）被认为是替代哈伯-博世方法的一种环保且可行的方法。寻找有效的 ENRR 催化剂是一个极其重要但具有挑战性的前提。在此，我们设计了具有氮空位的 g-CN 纳米片掺杂不对称硅-金属二聚体催化剂（SiM@CN），以解决氮的活化和还原问题。SiM@CN 概念催化剂在 ENRR 过程中可以结合硅基和金属基催化剂的优点。在所研究的催化剂中，SiMo@CN 和 SiRu@CN 对 ENRR 表现出最高的活性，具有超低的起始电位-0.20 和-0.39 V；同时，由于释放氢气相对困难，它们抑制了竞争的析氢反应（HER）。此外，SiRu@CN 表现出很强的疏水性，这对氨的生产非常有利。这项研究为不对称硅-金属二聚体催化剂提供了新的见解，并为开发双原子电催化剂提供了一种新方法。这种不对称二聚体策略可以应用于其他电催化能量转换反应中。
