Folic Acid Self-Assembly Enabling Manganese Single-Atom Electrocatalyst for Selective Nitrogen Reduction to Ammonia

• 作者: Xuewan Wang Dan Wu Suyun Liu Jiujun Zhang Xian-Zhu Fu Jing-Li Luo
• 来源期刊: 纳微快报（英文版）
• 年，卷（期）: 2021,（8）
• 页码范围: 163-174
• 页数: 12页
• 语种: 英文

摘要

Efficient and robust single-atom catalysts (SACs) based on cheap and earth-abundant elements are highly desirable for elec-trochemical reduction of nitrogen to ammonia (NRR) under ambi-ent conditions. Herein, for the first time, a Mn-N-C SAC consisting of isolated manganese atomic sites on ultrathin carbon nanosheets is developed via a template-free folic acid self-assembly strategy. The spontaneous molecular partial dissociation enables a facile fabrication process without being plagued by metal atom aggregation. Thanks to well-exposed atomic Mn active sites anchored on two-dimensional conductive carbon matrix, the catalyst exhibits excellent activity for NRR with high activity and selectivity, achieving a high Faradaic efficiency of 32.02％ for ammonia synthesis at - 0.45 V versus revers-ible hydrogen electrode. Density functional theory calculations unveil the crucial role of atomic Mn sites in promoting N2 adsorption, activation and selective reduction to NH3 by the distal mechanism. This work provides a simple synthesis process for Mn-N-C SAC and a good platform for understanding the structure-activity relationship of atomic Mn sites.