Jing Peng, Liu Peixin, Hu Minghao, Xu Xuan, Liu Baocang, Zhang Jun
School of Chemistry and Chemical Engineering, Inner Mongolia Engineering and Technology Research Center for Catalytic Conversion and Utilization of Carbon Resource Molecules, Inner Mongolia University, Hohhot, 010021, P. R. China.
Inner Mongolia Academy of Science and Technology, Hohhot, 010010, P. R. China.
Small. 2022 Jun;18(23):e2201200. doi: 10.1002/smll.202201200. Epub 2022 May 9.
Electrochemical nitrogen reduction powered by renewable electricity is a promising strategy to produce ammonia. However, the lack of efficient yet cheap electrocatalysts remains the biggest challenge. Herein, hybrid Cu O-CeO -C nanorods are prepared on copper mesh through a metal-organic framework template route. The Cu-loaded Ce-MOF is thermally converted to Cu O-CeO heterojunctions with interfacial Cu-[O ]-Ce structures embedded in carbon. Theoretical calculations reveal the lower formation energy of oxygen vacancies in Cu-[O ]-Ce structures than in the Cu O or CeO phase. The Cu-[O ]-Ce structures with oxygen vacancies enable the formation of interfacial electron-rich Cu(I) species which show significantly enhanced performance toward electrocatalytic nitrogen reduction with an NH yield of 6.37 × 10 µg s cm and a Faradaic efficiency of 18.21% in 0.10 m KOH at -0.3 V versus reversible hydrogen electrode. This work highlights the importance of modulation of charge distribution of Cu-based electrocatalysts to boost the activity toward nitrogen reduction.
由可再生电力驱动的电化学氮还原是一种很有前景的制氨策略。然而，缺乏高效且廉价的电催化剂仍然是最大的挑战。在此，通过金属有机框架模板路线在铜网上制备了混合的CuO-CeO₂-C纳米棒。负载铜的Ce-MOF经热转化为具有嵌入碳中的界面Cu-[O]-Ce结构的CuO-CeO₂异质结。理论计算表明，Cu-[O]-Ce结构中氧空位的形成能低于CuO或CeO₂相。具有氧空位的Cu-[O]-Ce结构能够形成界面富电子的Cu(I)物种，在相对于可逆氢电极-0.3 V的0.10 m KOH中，对电催化氮还原表现出显著增强的性能，NH₃产率为6.37×10⁻⁹ μg s⁻¹ cm⁻²，法拉第效率为18.21%。这项工作突出了调节铜基电催化剂电荷分布对提高氮还原活性的重要性。
