Li Xingchuan, Shen Peng, Luo Yaojing, Li Yunhe, Guo Yali, Zhang Hu, Chu Ke
School of Materials Science and Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, China.
School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, China.
Angew Chem Int Ed Engl. 2022 Jul 11;61(28):e202205923. doi: 10.1002/anie.202205923. Epub 2022 May 20.
Single-atom alloys hold great promise for electrocatalytic nitrogen reduction reaction (NRR), while the comprehensive experimental/theoretical investigations of SAAs for the NRR are still missing. Herein, PdFe single-atom alloy metallene, in which the Fe single atoms are confined on a Pd metallene support, is first developed as an effective and robust NRR electrocatalyst, delivering exceptional NRR performance with an NH yield of 111.9 μg h mg , a Faradaic efficiency of 37.8 % at -0.2 V (RHE), as well as a long-term stability for 100 h electrolysis. In-depth mechanistic investigations by theoretical computations and operando X-ray absorption/Raman spectroscopy indentify Pd-coordinated Fe single atoms as active centers to enable efficient N activation via N -to-Fe σ-donation, reduced protonation energy barriers, suppressed hydrogen evolution and excellent thermodynamic stability, thus accounting for the high activity, selectivity and stability of PdFe for the NRR.
单原子合金在电催化氮还原反应（NRR）方面具有巨大潜力，然而，针对NRR的单原子合金的全面实验/理论研究仍付诸阙如。在此，首次开发出一种PdFe单原子合金金属烯，其中铁单原子被限制在钯金属烯载体上，作为一种高效且稳定的NRR电催化剂，展现出卓越的NRR性能，NH产率为111.9 μg h mg ，在-0.2 V（RHE）时法拉第效率为37.8%，并具有长达100 h电解的长期稳定性。通过理论计算和原位X射线吸收/拉曼光谱进行的深入机理研究确定，钯配位的铁单原子为活性中心，通过N到Fe的σ供体作用实现高效的氮活化，降低质子化能垒，抑制析氢并具有出色的热力学稳定性，从而解释了PdFe对NRR的高活性、选择性和稳定性。
